Skip to main content

Congenital hydrocephalus: a review of recent advances in genetic etiology and molecular mechanisms

Abstract

The global prevalence rate for congenital hydrocephalus (CH) is approximately one out of every five hundred births with multifaceted predisposing factors at play. Genetic influences stand as a major contributor to CH pathogenesis, and epidemiological evidence suggests their involvement in up to 40% of all cases observed globally. Knowledge about an individual’s genetic susceptibility can significantly improve prognostic precision while aiding clinical decision-making processes. However, the precise genetic etiology has only been pinpointed in fewer than 5% of human instances. More occurrences of CH cases are required for comprehensive gene sequencing aimed at uncovering additional potential genetic loci. A deeper comprehension of its underlying genetics may offer invaluable insights into the molecular and cellular basis of this brain disorder. This review provides a summary of pertinent genes identified through gene sequencing technologies in humans, in addition to the 4 genes currently associated with CH (two X-linked genes L1CAM and AP1S2, two autosomal recessive MPDZ and CCDC88C). Others predominantly participate in aqueduct abnormalities, ciliary movement, and nervous system development. The prospective CH-related genes revealed through animal model gene-editing techniques are further outlined, focusing mainly on 4 pathways, namely cilia synthesis and movement, ion channels and transportation, Reissner’s fiber (RF) synthesis, cell apoptosis, and neurogenesis. Notably, the proper functioning of motile cilia provides significant impulsion for cerebrospinal fluid (CSF) circulation within the brain ventricles while mutations in cilia-related genes constitute a primary cause underlying this condition. So far, only a limited number of CH-associated genes have been identified in humans. The integration of genotype and phenotype for disease diagnosis represents a new trend in the medical field. Animal models provide insights into the pathogenesis of CH and contribute to our understanding of its association with related complications, such as renal cysts, scoliosis, and cardiomyopathy, as these genes may also play a role in the development of these diseases. Genes discovered in animals present potential targets for new treatments but require further validation through future human studies.

Background

Congenital hydrocephalus (CH) is characterized by the excessive accumulation of cerebrospinal fluid (CSF) in the brain at birth [1]. The incidence of CH is approximately 1/500 among young individuals and 2/500 among the elderly. It is a complex brain disorder with multiple etiological factors, including vitamin B or folic acid deficiency, intraventricular hemorrhage, viral infections, environmental influences, developmental anomalies, and genetic predisposition, often accompanied by structural brain abnormalities and neural dysfunction [2]. Common symptoms of hydrocephalus include gait disturbances, cognitive impairment, urinary dysfunction, seizures, abnormal reflexes, bradycardia and hypoventilation, headaches, vomiting, and visual impairments [3]. Among these factors contributing to CH development, global epidemiological data suggests that genetic factors account for more than 40% of cases [4, 5]. The annual medical costs associated with hydrocephalus are estimated at around $2 billion per year in the US alone, thus posing a significant economic and societal burden [6].

Though genetic factors contribute to up to 40% of cases of CH, precise genetic causes have only been identified in less than 5% of human cases [4]. There is a pressing need for a deeper understanding of the genetic components and mechanisms underlying CH, which has the potential to yield invaluable insights into its molecular and cellular etiology [7]. This review aims to consolidate existing evidence on the pathologic genes implicated in both human patients and animal models with respect to CH development. The goal is to stimulate novel approaches towards treating CH. Additionally, we discuss other developmental disorders and organ dysfunctions associated with genes related to hydrocephalus.

The production and circulation of CSF

CSF plays a critical role not only in providing mechanical support for the brain and spinal cord but also serves as a carrier for transporting metabolic waste and nutrients [8]. The healthy brain consists of three integrated components that collectively regulate CSF dynamics: CSF production, circulation, and absorption. These three components typically maintain equilibrium.

Approximately 80–90% of CSF is produced by the choroid plexus in the cerebral lateral ventricles [9, 10] (Fig. 1). Ion transporters on the basolateral membrane facing the blood and the apical membrane facing the ventricles are responsible for secreting and delivering ions such as Na+, Cl and HCO3 from the blood to the ventricles [11,12,13]. The remaining 10–20% of CSF production is attributed to the brain parenchymal system through exchange between CSF and interstitial fluid (ISF) in the capillary-astrocyte complex.

Fig. 1
figure 1

The production of CSF occurs through two distinct pathways: the choroid plexus and the brain parenchymal system. CSF can be absorbed by the subarachnoid space or glymphatic circulation, ultimately entering the dcLNs. CSF cerebrospinal fluid, dcLNs deep cervical lymphatic nodes, ISF interstitial fluid, mLVs meningeal lymphatic vessels

Most researchers have hypothesized that the circulation of CSF commences from the lateral ventricles, proceeds into the third ventricle, and then passes into the fourth ventricle through the midbrain cerebral aqueduct. The majority of CSF subsequently flows into the cisterna magna and cerebellopontine cisterns via the apertures of the fourth ventricle, namely, the median aperture and two lateral apertures. Ultimately, it is reabsorbed into the cerebral venous system through the arachnoid villi [14]. The extracranial lymphatic drainage pathway serves as a crucial component of CSF circulation, playing a pivotal role in maintaining homeostasis, buffering functions, and protective mechanisms of the central nervous system (CNS) [15]. As illustrated in Fig. 1, a significant volume of CSF drains into nasal lymph nodes and meningeal lymphatic vessels (mLVs), through which CSF is removed from intracranial spaces to extracranial regions and subsequently absorbed by the deep cervical lymphatic nodes (dcLNs) [16]. This intricate physiological process involves interactions among multiple molecules. Therefore, in subsequent sections, we will focus on pathological mechanisms related to molecular dysfunctions causing hydrocephalus. Disruption in any of these processes could lead to excessive accumulation of CSF and ventriculomegaly due to factors such as CSF overproduction, inefficient reabsorption into the systemic circulation, abnormal cilium-dependent flow, or obstruction within the ventricular system.

The main genetic target of CH in humans

Genes associated with CH in human cases are presented in Fig. 2, most of which are involved in Sylvius aqueduct (SA) defects, cilia growth and movement, and nervous system development. The Human Phenotype Ontology website predicts that 411 genes are related to “hydrocephalus” (HP:0000238). Among them, only 4 genes have been confirmed to be linked to CH: two X-linked genes [L1CAM (L1 cell adhesion molecule) and AP1S2 (adaptor-related protein complex 1 subunit sigma 2)] and two autosomal recessive genes [MPDZ (multiple PDZ domain crumbs cell polarity complex component) and CCDC88C (coiled-coil domain containing 88C)].

Fig. 2
figure 2

The genetic targets of CH in humans involve genes related to cilia movement, Sylvius aqueduct development, and nervous system growth in pathological cases of CH. CH congenital hydrocephalus, FOXJ1 forkhead box J1, CWH43 cell wall biogenesis 43 C-terminal homolog, AK9 adenylate kinase 9, AP1S2 adaptor related protein complex 1 subunit sigma 2, CCDC88C coiled-coil domain containing 88C, L1CAM L1 cell adhesion molecule, TR1M71 tripartite motif containing 71, SMARCC1 SWI/SNF related, matrix associated, actin dependent regulator of chromatin subfamily C member 1, PTCH1 patched 1, SHH sonic hedgehog, MPDZ multiple PDZ domain crumbs cell polarity complex component, CRB2 crumbs cell polarity complex component 2

SA stenosis, which connects the third and fourth ventricles, is responsible for the majority of cases of non-syndromic CH. Approximately 5–15% of cases are associated with X-linked variations of L1CAM, known as L1 syndrome. L1CAM encodes a transmembrane glycoprotein belonging to the immunoglobulin superfamily of cell adhesion molecules, and it plays important roles in neuronal adhesion, migration, growth cone morphology, neurite outgrowth, and myelination. Another separate X-linked syndrome called Fried-Pettigrew syndrome [Online Mendelian Inheritance in Man (OMIM): 304,340], is characterized primarily by intellectual disability, basal ganglia iron or calcium deposition, and hydrocephalus due to AP1S2 variation [17,18,19]. Variations in MPDZ and CCDC88C share many neuropathological similarities including atresia of both SA and the central canal of the medulla with recessive forms of CH (OMIM: 615,219 and OMIM: 236,600 respectively). Both genes colocalize at the apical cell junction in the neural plate, CCDC88C directly interacts with MPDZ and cooperates to promote apical cell constriction during neurulation [20, 21]. MPDZ is essential for maintaining ependymal integrity, loss of MPDZ leads to ependymal denudation accompanied by reactive astrogliosis and SA stenosis [22]. Additionally, mutations in MPDZ can cause abnormally high permeability in choroid plexus epithelial cell monolayers [23].

Moreover, this section also provides a summary of the mutation genes identified through gene sequencing technology in cases of hydrocephalus and related diseases, which require further validation to establish their causal involvement in hydrocephalus. Regarding SA development-related genes, CRB2 encodes the crumbs cell polarity complex component 2, originally primarily associated with renal anomalies such as renal tubular or glomerular microcysts. Recently, Tessier et al. [24] reported that biallelic CRB2 variations are also strongly linked to hydrocephalus, resulting from atresia of the SA and central canal aqueduct of the medulla.

For the genes related to cilia growth and motility, CWH43 (cell wall biogenesis 43 C-terminal homolog) is highly expressed in ciliated ependymal and choroid plexus cells, where it regulates the membrane localization of glucose-6-phosphate isomerase (GPI)‐anchored proteins in mammalian cells. Yang et al. [25] found that approximately 15% of patients with idiopathic normal pressure hydrocephalus (iNPH) carry heterozygous loss-of-function deletions in CWH43. Similarly, mice with Cwh43 deletions could develop communicating hydrocephalus, gait dysfunction, and abnormalities in choroid plexus and ependymal cells. The mutation of CWH43 affects the number of ependymal cilia and the apical/basal targeting of GPI‐anchored proteins in ventricular multi-ciliated epithelial cells, which may contribute to the development of iNPH. AK9, encoding adenylate kinase 9, was also suggested to be involved in iNPH. A damaging mutation in AK9 was detected in 9.6% of iNPH patients [26]. Mice with Ak9 mutation exhibit decreased cilia motility and beat frequency, as a result of communicating hydrocephalus and balance impairment. Dysfunction of the FOXJ1 (forkhead box J1) triggers autosomal dominant motile ciliopathies affecting many organ systems, including brain ventricles leading mainly to abnormal ventricular ciliary motility in CH [27]. CC2D2A (coiled-coil and C2 domain containing 2A) mutations are a relatively common cause of Joubert syndrome, a ciliopathy characterized by distinctive brain malformation and developmental delay. Patients with CC2D2A mutations often present with hydrocephalus or epilepsy [28]. Furthermore, Munch et al. [29] investigation revealed that 14 genes are involved in ciliogenesis, CELSR2 (cadherin EGF LAG seven-pass G-type receptor 2), CENPF (centromere protein F), DNAI1 (dynein axonemal intermediate chain 1), DNAH5 (dynein axonemal heavy chain 5), FLNA (filamin A), FUZ (fuzzy planar cell polarity protein), IFT172 (intraflagellar transport 172), LRP6 (LDL receptor-related protein 6), MPDZ, NOTCH2 (Notch receptor 2), PIK3R2 (phosphoinositide-3-kinase regulatory subunit 2), PTCH1 (patched 1), TRIM71 (tripartite motif containing 71), and VANGL2 (VANGL planar cell polarity protein 2).

In relation to the nervous system’s function, TRIM71, SMARCC1 (SWI/SNF related, matrix-associated, actin-dependent regulator of chromatin subfamily C member 1), PTCH1, and SHH (sonic hedgehog) play crucial roles in both neural tube development as well as neural stem cell (NSC) growth. Furey et al. [30] identified mutations within these aforementioned 4 genes among 125 CH trios and 52 independent probands through whole exome sequencing (WES). SMARCC1 encodes for SWI/SNF-related, matrix-associated, actin-dependent regulator of chromatin, subfamily C, member 1 (BAF155) which is a chromatin remodeling protein, its mutation results in CH phenotype associated with defects during neural tube development [31,32,33]. Additionally, 6 other genes, ASTN2 (astrotactin 2), B3GALNT2 (beta-1,3-N-acetylgalactosaminyltransferase 2), DAG1 (dystroglycan 1), NF1 (neurofibromin 1), ROBO1 (roundabout guidance receptor 1), and SMARCC1 participate in processes related to neuronal formation [29].

In addition, several genes have been identified as being related to hydrocephalus, but the reporting of this relationship has been incomplete. MMACHC (metabolism of cobalamin associated C) mutation with c.609G > A is most frequently observed in patients with cobalamin C deficiency (cblC). Recent research has shown that the homologous mutation MMACHC c.609G > A often leads to irreversible brain disorders such as developmental delay, seizures, and hydrocephalus [34]. Furthermore, a study of 27 CH families revealed that the WDR81 (WD repeat domain 81) and EML1 (EMAP like 1) genes are associated with CH [35]. Another study involving 381 sporadic CH cases (232 trios) identified several new risk genes of CH including PIK3CA (phosphatidylinositol-4,5-bisphosphate 3-kinase catalytic subunit alpha), PTEN (phosphatase and tensin homolog), mTOR (mechanistic target of rapamycin kinase), FMN2 (formin 2), and FXYD2 (FXYD domain-containing ion transport regulator 2) [19]. Additionally, a study of 110 infantile hydrocephalus cases indicated that ZEB1 (zinc finger E-box binding homeobox 1), SBF2 (SET binding factor 2), and GNAI2 (G protein subunit alpha i2) were over-represented and might affect the signaling pathways involved in infantile hydrocephalus formation [36].

Overall, due to limited data and research, the current findings can only account for less than 5% of primary CH cases [37]. Further genome sequencing of large, well-phenotype cohorts is necessary to gain a deeper understanding of the molecular and cellular etiology of CH.

The main genetic targets of CH in animal models

Animal models of CH exhibit numerous histopathological similarities to humans, making them valuable for studying the genetics and pathogenesis of CH. Many genetic loci associated with hydrocephalus have been identified in animal models [38]. In this section, we provide a summary of CH-related genes discovered in animal models, most of which are related to cilia synthesis and movement, ion transportation, RF synthesis, cell apoptosis, and neurogenesis (Fig. 3).

Fig. 3
figure 3

Genes associated with CH identified in animal models. In zebrafish and mouse models, genes linked to the development of hydrocephalus can be categorized into 4 distinct groups: cilia synthesis and movement-related, ion transporter-related, RF synthesis-related, cell apoptosis and neurogenesis-related, etc. RF Reissner’s fiber, CH congenital hydrocephalus, CNS central nervous system, CaV1.2 calcium voltage-gated channel subunit alpha1 C, Calb2 calbindin 2, Atp1a3 ATPase Na+/K+ transporting subunit α3, Slc41a1 solute carrier family 41 members 1, Pank2 pantothenate kinase 2, Ccdc85c coiled-coil domain containing 85C, Lgi1b leucine-rich glioma inactivated 1b, Ecrg4 esophageal cancer related gene 4, Wdr16 cilia and flagella associated protein 52, Nphp7 nephrocystin 7, Ccp5 cytosolic carboxypeptidases 5, Exoc5 cxocyst complex component 5, Msx1 Msh homeobox 1, Hrg1 solute carrier family 48 member 1, b-Pix Rho guanine nucleotide exchange factor (GEF) 7b

Cilia-related genes

Ciliated structures composed of microtubules form elongated protrusions on cellular membranes, they can be found in various cell types including ependymal cells. Cilia can be classified into two categories: primary cilium which serves primarily as a sensor for signal transduction [39], and motile cilium is found predominantly on specialized cells responsible for fluid movement or cell propulsion through outer dynein arms (ODA) and inner dynein arms (IDA) [40]. Malfunctioning ciliary activity may lead to genetic developmental disorders associated with primary ciliary dyskinesia (PCD), leading to conditions such as infertility, developmental anomalies, hydrocephalus, and auditory issues along with compromised respiratory pathogens clearance leading susceptibility towards infections causing persistent coughing and dyspnea [41]. Ependymal cells are located in the superficial layer of the cerebral ventricle walls and the central canal of the spinal cord. The cilia on these cells play a role in producing and circulating CSF as well as contributing to nerve regeneration. Both primary and motile cilia are involved in hydrocephalus through distinct mechanisms related to their physiological functions. Cilia distributed in various regions of the ventricles work together to maintain the directional flow of CSF. Growing evidence indicated that coordinated beating of motile cilia generates significant force, propelling CSF production and circulation within brain ventricles [42, 43]. Impairment of ciliary motor function can disrupt the balance between CSF production and circulation, resulting in the accumulation of CSF in the ventricles. Table 1 presents a list of 28 genes that regulate the structure and function of cilia [44,45,46,47,48,49,50,51,52,53,54,55,56,57,58,59,60,61,62,63,64,65,66,67,68,69,70,71,72,73,74].

Table 1 List of potential CH-related genes in animal models

Wdr16 (cilia and flagella-associated protein 52) plays a crucial role in cilia-related signal transduction. In zebrafish, severe hydrocephalus was observed in the Wdr16 gene knockdown zebrafish. It is noteworthy that hydrocephalus was the phenotype of Wdr16 disruption in zebrafish, but ependymal disorganization or impaired ciliary motility was not observed [44, 45]. It’s speculated that Wdr16 regulates hydrocephalus through cilia-mediated cell polarity effects such as water homeostasis or osmoregulation. Wdr78 (dynein axonemal intermediate chain 4) encodes a motile cilium-specific protein involved in the assembly of the axon dynein complex and ciliary movement. Depletion of Wdr78 in mice caused defects in ependymal cilia, while Wdr78 morphants zebrafish exhibited ciliopathy-associated phenotypes such as hydrocephalus, pronephric cysts, or abnormal otoliths [46]. Therefore, studies have shown that depletion of Wdr78 leads to abnormal ciliary beat function of ectodermal cells by affecting the dynein-f assembly. Nphp7 (nephrocystin 7) is a type of transcription factor and has been found to physically interact with Bardet-Biedl syndrome 1 (BBS1). A previous study indicated that hydrocephalus and pronephric cysts were displayed in the Nphp7 zebrafish morphants [47]. It is noteworthy that the deletion of Nphp7 revealed an astonishingly impaired ciliary motility.

Ion channels and ion transporter-related genes

Ion transporters play important roles in the process of CSF secretion. Due to the unidirectional nature of ion movement, transporters located on the basement membrane side differ from those on the apical membrane side. These transporters effectively maintain internal homeostasis and balance of Na+, Cl, and HCO3, which in turn regulate CSF secretion. In this section, we examine 6 genes associated with ion transporter function, whose dysfunction could impact CSF secretion and lead to hydrocephalus (Table 1) [75,76,77,78,79].

Calb2 (calbindin 2) belongs to the troponin C superfamily of Ca2+ binding protein and is involved in Ca2+ transportation. In zebrafish, Calb2a and Calb2b are highly expressed in the CNS and peripheral nervous system, where they play a crucial role in regulating synaptic calcium concentration, thus contributing significantly to nervous system development. The combined loss of Calb2a and Calb2b leads to severe hydrocephalus, axial curvature defect, and yolk sac edema in zebrafish due to impaired neural tube folding and disorganized midbrain-hindbrain boundary [76]. Atp1a3 (ATPase Na+/K+ transporting subunit α3) encodes an essential ion-transporting enzyme that regulates transmembrane Na+ and K+ gradients, playing a vital role in electrical excitation transmission of nerve and muscles. The Atp1a3 knockdown in zebrafish can result in hydrocephalus due to disrupted transmembrane ion transport [78]. Slc41a1 (solute carrier family 41 member 1) encodes Mg2+ transporter proteins located at the base membrane that participate in the transmembrane transport of Mg2+. Knockdown of Slc41a1 with morpholino leads to body curvature, hydrocephalus, and kidney cysts in zebrafish as a result of disrupted intracellular Mg2+ homeostasis caused by blocked transmembrane Mg2+ transport [79].

CNS-related genes

CH is not only a disorder of CSF dynamics, but also a brain disorder that leads to severe neurological impairment [80]. Most cells in the developing mammalian brain derive from the ventricular (VZ) and subventricular (SVZ) zones. The VZ consists of multipotent radial glia/NSCs, while the SVZ is composed of rapidly proliferating neural precursor cells (NPCs) [81]. These zones are crucial for neurodevelopment and any disruption, particularly within the VZ, can lead to stenosis or obliteration of the cerebral aqueduct of Sylvius, ultimately resulting in hydrocephalus [82,83,84]. This disturbance not only affects CSF flow but also simultaneously impairs the function of NSCs and ependymal cells, thereby linking hydrocephalus with abnormal neurogenesis [85,86,87]. Moreover, defects in membrane protein transporter-related genes could disrupt NSCs, leading to CH and associated cerebral malformations [1, 88,89,90]. Rodríguez et al. [82] proposed that gene mutations associated with cell junction proteins’ transport in NSCs could lead to the disruption of VZ, thereby resulting in aqueduct stenosis and hydrocephalus. NSCs play an important role in the growth of neurons and glial cells in the CNS [91, 92]. The dysfunction of NSC function hinders the polarity, proliferation, and differentiation of neurons. It is worth noting that NSC injury can also induce neurological disorders, such as cortical dysfunction, hydrocephalus, and periventricular heterotopia [91, 93]. Additionally, it is noteworthy that apoptosis within the CNS may impact neuronal development, resulting in hydrocephalus and nasal malformations [94]. In this section, we review 7 genes associated with CNS, whose dysfunction could contribute to hydrocephalus (Table 1) [82, 95,96,97,98,99,100].

Pank2 (pantothenate kinase 2) encodes a protein belonging to the pantothenate kinase family and plays an essential role in cellular coenzyme A biosynthesis. Pank2 morphant in zebrafish induced abnormal phenotypes including disrupted brain morphology, hydrocephalus, and edema in the heart region [95]. Downregulation of Pank2 significantly impacts the development of neurons in the CNS and neuronal cells. Ecrg4 (esophageal cancer-related gene 4) regulates the secretion of neuropeptides and is mainly expressed in the choroid plexus (CP) epithelial cells, brain ventricular, and central canal cells of the spinal cord. The product of Ecrg4, Augurin, contributes to the development of CNS and participates in the proliferation of NSC and NPC. Knockdown of Ecrg4 using morpholino in zebrafish induced a hydrocephalus-like phenotype related to the damage of CNS [96].

Subcommissural organ (SCO)-RF-related genes

RF, a network of threadlike glycoproteins suspended within the CSF, plays a pivotal role in the homeostatic regulation of the brain’s internal environment, by binding to and facilitating the transport and clearance of monoaminergic compounds. It is produced and released from the SCO of the brain, an active gland during development in most species including humans [101]. The SCO is an ependymal structure located at the roof of the third ventricle and the entrance to the mesencephalic aqueduct [102,103,104]. The RF extends through the SA, fourth ventricle, and central canal of the spinal cord to reach the caudal ampulla or fifth ventricle located at the end of the central canal [101]. Dysfunction of the SCO-RF complex is closely related to hydrocephalus phenotypes [103, 105]. Evidence suggested that the absence of RF or immunological damage to SCO could lead to stenosis or obliteration of cerebral aqueduct and defects in the neural canal (NCa), thereby impairing CSF circulation resulting in CH [106,107,108]. Moreover, the role of RF extends to neural development and axonal guidance, with its deficiency being associated with morphological brain defects, highlighting its multifaceted contribution to both normal physiology and disease pathology [88]. It is worth noting that RF is exclusively present in animals, except for humans. In humans, the secretory capacity of the SCO is robust in 3–5-month-old fetuses; however, it regresses significantly in 9-month fetuses. By 1-year-old, secretory ependymal cells shrink and cluster into islets interspersed with non-secretory cuboidal ependyma. This regression continues through childhood, limiting secretory parenchyma to scattered islets by the ninth year. Despite the absence of RF in humans, SCO-spondin, the unpolymerized form of RF, is present and soluble in CSF, thus impacting brain development [109]. It also participates in certain aspects of neurogenesis, such as the cell cycle of NSCs, neuronal differentiation, and axon pathfinding [104]. In this section, we discuss 2 genes linked to RF function that contribute to the development of hydrocephalus (Table 1) [105, 110].

Camal encodes a protein associated with cell adhesion. Camel regulates the development of brain ventricular, and loss of camel function in zebrafish leads to the manifestation of hydrocephalus and scoliosis. Deletion of camel has been shown to result in hydrocephalus due to defects in RF synthesis, resulting from abnormal CSF flow [105]. Msx1 (Msh homeobox 1) is involved in regulating DNA-binding transcription factor activity and is widely expressed in neuroepithelial cells. Msx1 mutants exhibit severe hydrocephalus at birth, accompanied by abnormal SCO development. Additionally, RF was found to be absent in Msx1 mutant mice [110]. This suggests that Msx1 mutants inhibit RF synthesis by affecting normal SCO development, thereby affecting CSF flow.

Others

Table 1 also highlights five additional genes and small molecular substances linked to hydrocephalus [111,112,113,114,115]. However, the mechanisms by which these genes influence the progression of hydrocephalus are not fully understood or categorized as mentioned earlier. Furthermore, the inflammatory/immune response may also be associated with the progression and severity of hydrocephalus [2, 116]. In the hyh mice and HTx rats (two animal models of fetal-onset hydrocephalus), the onset of ventricle disruption is correlated with the infiltration of macrophages and lymphocytes into denuded.

The expression of β-Pix [Rho guanine nucleotide exchange factor (GEF) 7b] is widespread in both the brain and blood vessels, where it plays a role in regulating cerebral vascular stability. In zebrafish, mutation of the β-Pix gene can lead to obvious hydrocephalus and severe intracranial hemorrhage during early embryonic development. It has been hypothesized that deleting β-Pix may disrupt vascular stability, potentially affecting CSF circulation [112]. Thioredoxin1 is an antioxidant protein with reactive oxygen species (ROS) scavenging capabilities that govern processes such as cell proliferation, migration, apoptosis, and inflammation. Zebrafish injected with thioredoxin1 morpholine exhibit hydrocephalus and midbrain malformations [115]. Deletion of thioredoxin1 triggers a significant increase in ventricular epithelial cell apoptosis while disrupting vascular endothelial cell migration, ultimately leading to hydrocephalus.

Discussion

In this review, we have comprehensively summarized the genetic factors and molecular mechanisms of CH in both human subjects and animal models. The results from human sequencing and validated genes showed that these genes are related to dysfunction of the central system, impaired cilia movement, and abnormalities in SA. By utilizing animal models such as mice and zebrafish, it becomes feasible to further investigate additional genes related to hydrocephalus pathology. These genes can be systematically classified into 4 principal groups: those linked to ciliary function, ion transport, CNS function, and RF synthesis. Genes related to ciliary function play an important role in regulating the synthesis, formation, and movement of cilia, which is closely connected with CSF absorption. Ion transporter-related genes primarily disrupt homeostasis by dysregulating the ions’ transportation processes, thus impacting CSF secretion. Mutation in CNS function-related genes predominantly affects the development, function, and apoptosis of nerve cells, which might result in potential disturbances in brain morphology. Additionally, the RF synthesis-related genes dysregulate the formation and morphology of NCa, influencing CSF circulation. The identification of these genes in CH animal models provides valuable resources for validation within larger clinical cohorts of CH patients.

Genetic insights hold profound significance in the management of CH. The pathogenesis of this complex disease may be closely linked to multiple gene variants. Genetic research aids in identifying these key gene variants, thereby unraveling the underlying mechanisms of the disease and paving the way for innovative treatment approaches [117]. For instance, if a specific genetic variant is found to be intricately associated with the disease, gene-editing techniques or gene therapy can be employed to correct this variant, ultimately aiming to cure the condition [118,119,120]. Furthermore, genetic understanding promotes personalized healthcare. As each individual has a unique genome, responses to illnesses and treatment outcomes naturally differ. Genetic research enables tailored therapies based on a patient’s genotype, optimizing treatment efficiency and minimizing adverse effects [121]. Moreover, genetic insights facilitate more accurate disease prediction and risk assessment. Genetic screenings allow us to anticipate an individual’s susceptibility to certain illnesses, enabling proactive preventive measures. This prediction is particularly crucial for genetic conditions such as CH. In conclusion, genetic insights offer immense potential to revolutionize disease treatment. As genetic research advances and technology evolves, we are poised to deliver more precise and effective medical care in the foreseeable future. Nevertheless, it is crucial to recognize that genetics do not hold all the answers, they address only a portion of health conditions. Hence, a holistic approach encompassing genetics as well as environment and lifestyle factors is essential for devising comprehensive treatment plans.

Addressing the complexities associated with CH necessitates developing a multimodal detection approach that integrates both clinical observations along radiological phenotypic characteristics alongside genotypic analysis for effective implementation within a clinical setting. This comprehensive approach plays a pivotal role in augmenting diagnostic precision and specificity, crucial when dealing with conditions where initial symptoms may not manifest at birth but evolve gradually over time. The utilization of clinical radiological medical imaging technology like CT as well as MRI offers substantial benefits, particularly in identifying structural anomalies within the brain including aqueduct stenosis, Dandy-Walker malformation, arachnoid cysts, and neural tube defects. Additionally, the insight provided by genotype data facilitates a deeper understanding of the onset and progression mechanisms related to CH pathology. However, it should be noted that genetic analysis alone may have limitations when elucidating complex presentations involving skull morphology, extracranial structures, and skeletal deformities. Therefore, a synergistic amalgamation encompassing genotype data along with detailed examination through clinical and radiologic means holds promise for expediting precise disease identification. Zhang et al. [122] integrated key findings from their study which involved combining patient-specific traits, and molecular analyses via neuroimaging modalities such as MRI/CT scans, gene mutation tests, and metabolic assessments. Moreover, Rijken et al. [123] demonstrated how 3D-CT reconstruction technology played an indispensable role in delineating morphometric changes in foramen magnum configuration as well as the presence of ventriculomegaly among pediatric patients diagnosed with craniosynostosis; this technique exhibits considerable potential for facilitating CH diagnostics. Consequently, this multimodal detection strategy, involving integration between radiologically derived phenotypes and genotype analytics, serves not only to enhance diagnostic precision and treatment efficacy but also paves the way for tailored medical interventions catering to individual patient needs. With ongoing advancements in technology-driven genomic research coupled with expanding horizons within clinical applications, it is anticipated that future management strategies will enable more accurate and effective treatment across diverse spectrums of ailments.

The phenotypic manifestations of genetic defects are remarkably diverse and complex. Pathogenic genes associated with hydrocephalus may also present in other tissues or organs, leading to a range of comorbidities. For instance, dysfunctional ciliary genes can also trigger renal cysts and scoliosis [46, 48, 49, 54, 56, 58]. Additionally, the loss of function of the SLC25A4 gene can lead to severe cardiomyopathy, scoliosis, cataracts, and depression [124]. Understanding the associated complications of hydrocephalus is essential for identifying the underlying pathology and implementing personalized treatment. If patients exhibit symptoms of hydrocephalus, early intervention, and targeted treatments should be provided to prevent associated comorbidities.

Further research into the genetic and pathogenesis of CH will facilitate the development of animal models for investigating drug treatment options. Currently, the field of drug therapy for CH remains largely unexplored, and establishing effective animal models of hydrocephalus provides a platform for exploring potential drug targets.

Conclusions

In this review, we have provided a comprehensive summary of recent discoveries regarding the genetic targets of CH in both human and animal models. In addition to the 4 confirmed genes associated with CH (X-linked genes L1CAM and AP1S2, autosomal recessive MPDZ, and CCDC88C). We have also reviewed 35 genes identified through gene sequencing in human cases, as well as numerous related genes in the CH animal model. These findings warrant further validation through extensive clinical studies involving a large cohort of CH patients. The implicated genes primarily participate in 4 pathways and may contribute to comorbidities affecting other organ functions where these related genes are expressed.

Availability of data and materials

Not applicable.

Abbreviations

AP1S2:

Adaptor-related protein complex 1 subunit sigma 2

AK9:

Adenylate kinase 9

CCDC88C:

Coiled-coil domain-containing 88C

CC2D2A:

Coiled-coil and C2 domain containing 2A

CH:

Congenital hydrocephalus

CNS:

Central nervous system

CP:

Choroid plexus

CRB2:

Crumbs cell polarity complex component 2

CSF:

Cerebral spinal fluid

CWH43:

Cell wall biogenesis 43 C-terminal homolog

dcLNs:

Deep cervical lymphatic nodes

EC:

Ependymal cell

GPI:

Glucose-6-phosphate isomerase

IDA:

Inner dynein arms

iNPH:

Idiopathic normal pressure hydrocephalus

ISF:

Interstitial fluid

L1CAM:

L1 cell adhesion molecule

mLVs:

Meningeal lymphatic vessels

MMACHC:

Metabolism of cobalamin-associated C

MPDZ:

Multiple PDZ domain crumbs cell polarity complex component

NCa:

Neural canal

NSPC:

Neural stem/progenitor cells

NSC:

Neural stem cell

NPC:

Neural progenitor cell

ODA:

Outer dynein arms

PCD:

Primary ciliary dyskinesia

PCP:

Planar cell polarity

PTCH1:

Patched 1

RF:

Reissner’s fiber

RGC:

Radial glial cells

SA:

Sylvius aqueduct

SCO:

Subcommissural organ

SMARCC1:

SWI/SNF related, matrix associated, actin dependent regulator of chromatin subfamily C member 1

SVZ:

Subventricular zone

TRIM71:

Tripartite motif containing 71

VZ:

Ventricular zone

WES:

Whole exome sequencing

References

  1. Genetic and Rare Diseases Information Center (GARD). Congenital hydrocephalus. 2024. Accessed Jul 10, 2024. https://rarediseases.info.nih.gov/diseases/6682/congenital-hydrocephalus.

  2. Karimy JK, Reeves BC, Damisah E, Duy PQ, Antwi P, David W, et al. Inflammation in acquired hydrocephalus: pathogenic mechanisms and therapeutic targets. Nat Rev Neurol. 2020;16(5):285–96.

    Article  PubMed  PubMed Central  Google Scholar 

  3. Hochstetler A, Raskin J, Blazer-Yost BL. Hydrocephalus: historical analysis and considerations for treatment. Eur J Med Res. 2022;27(1):168.

    Article  PubMed  PubMed Central  Google Scholar 

  4. Ross ME. Unlocking the genetic complexity of congenital hydrocephalus. Nat Med. 2020;26(11):1682–3.

    Article  CAS  PubMed  Google Scholar 

  5. Varagur K, Sanka SA, Strahle JM. Syndromic hydrocephalus. Neurosurg Clin N Am. 2022;33(1):67–79.

    Article  PubMed  PubMed Central  Google Scholar 

  6. Kahle KT, Kulkarni AV, Limbrick DD Jr, Warf BC. Hydrocephalus in children. Lancet. 2016;387(10020):788–99.

    Article  PubMed  Google Scholar 

  7. Kahle KT, Klinge PM, Koschnitzky JE, Kulkarni AV, Macaulay N, Robinson S, et al. Paediatric hydrocephalus. Nat Rev Dis Primers. 2024;10(1):35.

    Article  PubMed  Google Scholar 

  8. Fame RM, Lehtinen MK. Emergence and developmental roles of the cerebrospinal fluid system. Dev Cell. 2020;52(3):261–75.

    Article  CAS  PubMed  Google Scholar 

  9. Saunders NR, Dziegielewska KM, Fame RM, Lehtinen MK, Liddelow SA. The choroid plexus: a missing link in our understanding of brain development and function. Physiol Rev. 2023;103(1):919–56.

    Article  CAS  PubMed  Google Scholar 

  10. Robert SM, Reeves BC, Kiziltug E, Duy PQ, Karimy JK, Mansuri MS, et al. The choroid plexus links innate immunity to CSF dysregulation in hydrocephalus. Cell. 2023;186(4):764-85.e21.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  11. Wright EM. Transport processes in the formation of the cerebrospinal fluid. Rev Physiol Biochem Pharmacol. 1978;83:3–34.

    CAS  PubMed  Google Scholar 

  12. Macaulay N, Keep RF, Zeuthen T. Cerebrospinal fluid production by the choroid plexus: a century of barrier research revisited. Fluids Barriers CNS. 2022;19(1):26.

    Article  PubMed  PubMed Central  Google Scholar 

  13. Oernbo EK, Steffensen AB, Razzaghi Khamesi P, Toft-Bertelsen TL, Barbuskaite D, Vilhardt F, et al. Membrane transporters control cerebrospinal fluid formation independently of conventional osmosis to modulate intracranial pressure. Fluids Barriers CNS. 2022;19(1):65.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  14. Fang Y, Huang L, Wang X, Si X, Lenahan C, Shi H, et al. A new perspective on cerebrospinal fluid dynamics after subarachnoid hemorrhage: from normal physiology to pathophysiological changes. J Cereb Blood Flow Metab. 2022;42(4):543–58.

    Article  CAS  PubMed  Google Scholar 

  15. Proulx ST. Cerebrospinal fluid outflow: a review of the historical and contemporary evidence for arachnoid villi, perineural routes, and dural lymphatics. Cell Mol Life Sci. 2021;78(6):2429–57.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  16. Ahn JH, Cho H, Kim JH, Kim SH, Ham JS, Park I, et al. Meningeal lymphatic vessels at the skull base drain cerebrospinal fluid. Nature. 2019;572(7767):62–6.

    Article  CAS  PubMed  Google Scholar 

  17. Wallis M, Baumer A, Smaili W, Jaouad IC, Sefiani A, Jacobson E, et al. Surprisingly good outcome in antenatal diagnosis of severe hydrocephalus related to CCDC88C deficiency. Eur J Med Genet. 2018;61(4):189–96.

    Article  PubMed  Google Scholar 

  18. Allocco AA, Jin SC, Duy PQ, Furey CG, Zeng X, Dong W, et al. Recessive inheritance of congenital hydrocephalus with other structural brain abnormalities caused by compound heterozygous mutations in ATP1A3. Front Cell Neurosci. 2019;13:425.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  19. Jin SC, Dong W, Kundishora AJ, Panchagnula S, Moreno-De-Luca A, Furey CG, et al. Exome sequencing implicates genetic disruption of prenatal neuro-gliogenesis in sporadic congenital hydrocephalus. Nat Med. 2020;26(11):1754–65.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  20. Marivin A, Garcia-Marcos M. DAPLE and MPDZ bind to each other and cooperate to promote apical cell constriction. Mol Biol Cell. 2019;30(16):1900–10.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  21. Marguet F, Vezain M, Marcorelles P, Audebert-Bellanger S, Cassinari K, Drouot N, et al. Neuropathological hallmarks of fetal hydrocephalus linked to CCDC88C pathogenic variants. Acta Neuropathol Commun. 2021;9(1):104.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  22. Feldner A, Adam MG, Tetzlaff F, Moll I, Komljenovic D, Sahm F, et al. Loss of Mpdz impairs ependymal cell integrity leading to perinatal-onset hydrocephalus in mice. EMBO Mol Med. 2017;9(7):890–905.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  23. Yang J, Simonneau C, Kilker R, Oakley L, Byrne MD, Nichtova Z, et al. Murine MPDZ-linked hydrocephalus is caused by hyperpermeability of the choroid plexus. EMBO Mol Med. 2019. https://doi.org/10.15252/emmm.201809540.

    Article  PubMed  PubMed Central  Google Scholar 

  24. Tessier A, Roux N, Boutaud L, Lunel E, Hakkakian L, Parisot M, et al. Bi-allelic variations in CRB2, encoding the crumbs cell polarity complex component 2, lead to non-communicating hydrocephalus due to atresia of the aqueduct of sylvius and central canal of the medulla. Acta Neuropathol Commun. 2023;11(1):29.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  25. Yang HW, Lee S, Yang D, Dai H, Zhang Y, Han L, et al. Deletions in CWH43 cause idiopathic normal pressure hydrocephalus. EMBO Mol Med. 2021;13(3):e13249.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  26. Yang HW, Lee S, Berry BC, Yang D, Zheng S, Carroll RS, et al. A role for mutations in AK9 and other genes affecting ependymal cells in idiopathic normal pressure hydrocephalus. Proc Natl Acad Sci USA. 2023;120(51):e2300681120.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  27. Wallmeier J, Frank D, Shoemark A, Nöthe-Menchen T, Cindric S, Olbrich H, et al. De novo mutations in FOXJ1 result in a motile ciliopathy with hydrocephalus and randomization of left/right body asymmetry. Am J Hum Genet. 2019;105(5):1030–9.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  28. Bachmann-Gagescu R, Ishak GE, Dempsey JC, Adkins J, Oday D, Phelps IG, et al. Genotype-phenotype correlation in CC2D2A-related Joubert syndrome reveals an association with ventriculomegaly and seizures. J Med Genet. 2012;49(2):126–37.

    Article  CAS  PubMed  Google Scholar 

  29. Munch TN, Hedley PL, Hagen CM, Bækvad-Hansen M, Geller F, Bybjerg-Grauholm J, et al. The genetic background of hydrocephalus in a population-based cohort: implication of ciliary involvement. Brain Commun. 2023;5(1):fcad004.

    Article  PubMed  PubMed Central  Google Scholar 

  30. Furey CG, Choi J, Jin SC, Zeng X, Timberlake AT, Nelson-Williams C, et al. De novo mutation in genes regulating neural stem cell fate in human congenital hydrocephalus. Neuron. 2018;99(2):302-14.e4.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  31. Al Mutairi F, Alzahrani F, Ababneh F, Kashgari AA, Alkuraya FS. A mendelian form of neural tube defect caused by a de novo null variant in SMARCC1 in an identical twin. Ann Neurol. 2018;83(2):433–6.

    Article  CAS  PubMed  Google Scholar 

  32. Singh AK, Allington G, Viviano S, Mcgee S, Kiziltug E, Ma S, et al. A novel SMARCC1 BAFopathy implicates neural progenitor epigenetic dysregulation in human hydrocephalus. Brain. 2024;147(4):1553–70.

    Article  PubMed  Google Scholar 

  33. Hourvitz N, Kurolap A, Mory A, Haratz KK, Kidron D, Malinger G, et al. SMARCC1 is a susceptibility gene for congenital hydrocephalus with an autosomal dominant inheritance mode and incomplete penetrance. Prenat Diagn. 2023;43(10):1374–7.

    Article  CAS  PubMed  Google Scholar 

  34. He R, Mo R, Shen M, Kang L, Song J, Liu Y, et al. Variable phenotypes and outcomes associated with the MMACHC c.609 G > A homologous mutation: long term follow-up in a large cohort of cases. Orphanet J Rare Dis. 2020;15(1):200.

    Article  PubMed  PubMed Central  Google Scholar 

  35. Shaheen R, Sebai MA, Patel N, Ewida N, Kurdi W, Altweijri I, et al. The genetic landscape of familial congenital hydrocephalus. Ann Neurol. 2017;81(6):890–7.

    Article  CAS  PubMed  Google Scholar 

  36. Mei HF, Dong XR, Chen HY, Lu YL, Wu BB, Wang HJ, et al. Genetic etiologies associated with infantile hydrocephalus in a Chinese infantile cohort. World J Pediatr. 2021;17(3):305–16.

    Article  CAS  PubMed  Google Scholar 

  37. Adle-Biassette H, Saugier-Veber P, Fallet-Bianco C, Delezoide AL, Razavi F, Drouot N, et al. Neuropathological review of 138 cases genetically tested for X-linked hydrocephalus: evidence for closely related clinical entities of unknown molecular bases. Acta Neuropathol. 2013;126(3):427–42.

    Article  CAS  PubMed  Google Scholar 

  38. Li J, Zhang X, Guo J, Yu C, Yang J. Molecular mechanisms and risk factors for the pathogenesis of hydrocephalus. Front Genet. 2021;12:777926.

    Article  CAS  PubMed  Google Scholar 

  39. Youn YH, Han YG. Primary cilia in brain development and diseases. Am J Pathol. 2018;188(1):11–22.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  40. Pellicciotta N, Hamilton E, Kotar J, Faucourt M, Delgehyr N, Spassky N, et al. Entrainment of mammalian motile cilia in the brain with hydrodynamic forces. Proc Natl Acad Sci U S A. 2020;117(15):8315–25.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  41. Horani A, Ferkol TW. Understanding primary ciliary dyskinesia and other ciliopathies. J Pediatr. 2021;230:15-22.e1.

    Article  PubMed  Google Scholar 

  42. Doetsch F, García-Verdugo JM, Alvarez-Buylla A. Cellular composition and three-dimensional organization of the subventricular germinal zone in the adult mammalian brain. J Neurosci. 1997;17(13):5046–61.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  43. Del Bigio MR. The ependyma: a protective barrier between brain and cerebrospinal fluid. Glia. 1995;14(1):1–13.

    Article  PubMed  Google Scholar 

  44. Ta-Shma A, Perles Z, Yaacov B, Werner M, Frumkin A, Rein AJ, et al. A human laterality disorder associated with a homozygous WDR16 deletion. Eur J Hum Genet. 2015;23(9):1262–5.

    Article  CAS  PubMed  Google Scholar 

  45. Hirschner W, Pogoda HM, Kramer C, Thiess U, Hamprecht B, Wiesmüller KH, et al. Biosynthesis of Wdr16, a marker protein for kinocilia-bearing cells, starts at the time of kinocilia formation in rat, and wdr16 gene knockdown causes hydrocephalus in zebrafish. J Neurochem. 2007;101(1):274–88.

    Article  CAS  PubMed  Google Scholar 

  46. Zhang Y, Chen Y, Zheng J, Wang J, Duan S, Zhang W, et al. Vertebrate Dynein-f depends on Wdr78 for axonemal localization and is essential for ciliary beat. J Mol Cell Biol. 2019;11(5):383–94.

    Article  CAS  PubMed  Google Scholar 

  47. Kim YH, Epting D, Slanchev K, Engel C, Walz G, Kramer-Zucker A. A complex of BBS1 and NPHP7 is required for cilia motility in zebrafish. PLoS One. 2013;8(9):e72549.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  48. Lyons PJ, Sapio MR, Fricker LD. Zebrafish cytosolic carboxypeptidases 1 and 5 are essential for embryonic development. J Biol Chem. 2013;288(42):30454–62.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  49. Pathak N, Austin-Tse CA, Liu Y, Vasilyev A, Drummond IA. Cytoplasmic carboxypeptidase 5 regulates tubulin glutamylation and zebrafish cilia formation and function. Mol Biol Cell. 2014;25(12):1836–44.

    Article  PubMed  PubMed Central  Google Scholar 

  50. Lobo GP, Fulmer D, Guo L, Zuo X, Dang Y, Kim SH, et al. The exocyst is required for photoreceptor ciliogenesis and retinal development. J Biol Chem. 2017;292(36):14814–26.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  51. Sasaki K, Shiba K, Nakamura A, Kawano N, Satouh Y, Yamaguchi H, et al. Calaxin is required for cilia-driven determination of vertebrate laterality. Commun Biol. 2019;2:226.

    Article  PubMed  PubMed Central  Google Scholar 

  52. Choi YJ, Halbritter J, Braun DA, Schueler M, Schapiro D, Rim JH, et al. Mutations of ADAMTS9 cause nephronophthisis-related ciliopathy. Am J Hum Genet. 2019;104(1):45–54.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  53. Holdener BC, Percival CJ, Grady RC, Cameron DC, Berardinelli SJ, Zhang A, et al. ADAMTS9 and ADAMTS20 are differentially affected by loss of B3GLCT in mouse model of Peters plus syndrome. Hum Mol Genet. 2019;28(24):4053–66.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  54. Chandrasekar G, Vesterlund L, Hultenby K, Tapia-Páez I, Kere J. The zebrafish orthologue of the dyslexia candidate gene DYX1C1 is essential for cilia growth and function. PLoS One. 2013;8(5):e63123.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  55. Cho KJ, Noh SH, Han SM, Choi WI, Kim HY, Yu S, et al. ZMYND10 stabilizes intermediate chain proteins in the cytoplasmic pre-assembly of dynein arms. PLoS Genet. 2018;14(3):e1007316.

    Article  PubMed  PubMed Central  Google Scholar 

  56. Jung E, Choi TI, Lee JE, Kim CH, Kim J. ESCRT subunit CHMP4B localizes to primary cilia and is required for the structural integrity of the ciliary membrane. FASEB J. 2020;34(1):1331–44.

    Article  CAS  PubMed  Google Scholar 

  57. Pathak N, Obara T, Mangos S, Liu Y, Drummond IA. The zebrafish fleer gene encodes an essential regulator of cilia tubulin polyglutamylation. Mol Biol Cell. 2007;18(11):4353–64.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  58. Mitchison HM, Schmidts M, Loges NT, Freshour J, Dritsoula A, Hirst RA, et al. Mutations in axonemal dynein assembly factor DNAAF3 cause primary ciliary dyskinesia. Nat Genet. 2012;44(4):381–9.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  59. Zhou W, Dai J, Attanasio M, Hildebrandt F. Nephrocystin-3 is required for ciliary function in zebrafish embryos. Am J Physiol Renal Physiol. 2010;299(1):F55-62.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  60. Bubenshchikova E, Ichimura K, Fukuyo Y, Powell R, Hsu C, Morrical SO, et al. Wtip and Vangl2 are required for mitotic spindle orientation and cloaca morphogenesis. Biol Open. 2012;1(6):588–96.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  61. Grimes DT, Boswell CW, Morante NF, Henkelman RM, Burdine RD, Ciruna B. Zebrafish models of idiopathic scoliosis link cerebrospinal fluid flow defects to spine curvature. Science. 2016;352(6291):1341–4.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  62. Hong E, Jayachandran P, Brewster R. The polarity protein Pard3 is required for centrosome positioning during neurulation. Dev Biol. 2010;341(2):335–45.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  63. Shenolikar S, Voltz JW, Minkoff CM, Wade JB, Weinman EJ. Targeted disruption of the mouse NHERF-1 gene promotes internalization of proximal tubule sodium-phosphate cotransporter type IIa and renal phosphate wasting. Proc Natl Acad Sci U S A. 2002;99(17):11470–5.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  64. Treat AC, Wheeler DS, Stolz DB, Tsang M, Friedman PA, Romero G. The PDZ protein Na+/H+ exchanger regulatory factor-1 (NHERF1) regulates planar cell polarity and motile cilia organization. PLoS One. 2016;11(4):e0153144.

    Article  PubMed  PubMed Central  Google Scholar 

  65. Wu C, Yang M, Li J, Wang C, Cao T, Tao K, et al. Talpid3-binding centrosomal protein Cep120 is required for centriole duplication and proliferation of cerebellar granule neuron progenitors. PLoS One. 2014;9(9):e107943.

    Article  PubMed  PubMed Central  Google Scholar 

  66. Mangos S, Lam PY, Zhao A, Liu Y, Mudumana S, Vasilyev A, et al. The ADPKD genes pkd1a/b and pkd2 regulate extracellular matrix formation. Dis Model Mech. 2010;3(5–6):354–65.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  67. Wodarczyk C, Rowe I, Chiaravalli M, Pema M, Qian F, Boletta A. A novel mouse model reveals that polycystin-1 deficiency in ependyma and choroid plexus results in dysfunctional cilia and hydrocephalus. PLoS One. 2009;4(9):e7137.

    Article  PubMed  PubMed Central  Google Scholar 

  68. Sussman CR, Ward CJ, Leightner AC, Smith JL, Agarwal R, Harris PC, et al. Phosphodiesterase 1A modulates cystogenesis in zebrafish. J Am Soc Nephrol. 2014;25(10):2222–30.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  69. Zhang T, Cui S, Xiong X, Liu Y, Cao Q, Xia XG, et al. PIH1D3-knockout rats exhibit full ciliopathy features and dysfunctional pre-assembly and loading of dynein arms in motile cilia. Front Cell Dev Biol. 2023;11:1282787.

    Article  PubMed  PubMed Central  Google Scholar 

  70. Wang X, Zhou Y, Wang J, Tseng IC, Huang T, Zhao Y, et al. SNX27 deletion causes hydrocephalus by impairing ependymal cell differentiation and ciliogenesis. J Neurosci. 2016;36(50):12586–97.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  71. Zhao X, Ge H, Xu W, Cheng C, Zhou W, Xu Y, et al. Lack of CFAP54 causes primary ciliary dyskinesia in a mouse model and human patients. Front Med. 2023;17(6):1236–49.

    Article  PubMed  Google Scholar 

  72. Abdelhamed Z, Vuong SM, Hill L, Shula C, Timms A, Beier D, et al. A mutation in Ccdc39 causes neonatal hydrocephalus with abnormal motile cilia development in mice. Development. 2018;145(1):dev54500.

    Article  Google Scholar 

  73. Mccoy CJ, Paupelin-Vaucelle H, Gorilak P, Beneke T, Varga V, Gluenz E. ULK4 and Fused/STK36 interact to mediate assembly of a motile flagellum. Mol Biol Cell. 2023;34(7):ar66.

    Article  PubMed  PubMed Central  Google Scholar 

  74. Man Y, Li W, Yap YT, Kearney A, Yee SP, Strauss JF 3rd, et al. Generation of floxed Spag6l mice and disruption of the gene by crossing to a Hprt-Cre line. Genesis. 2023;61(3–4):e23512.

    Article  CAS  PubMed  Google Scholar 

  75. Muntean BS, Jin X, Williams FE, Nauli SM. Primary cilium regulates CaV1.2 expression through Wnt signaling. J Cell Physiol. 2014;229(12):1926–34.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  76. Bhoyar RC, Jadhao AG, Sabharwal A, Ranjan G, Sivasubbu S, Pinelli C. Knockdown of calcium-binding calb2a and calb2b genes indicates the key regulator of the early development of the zebrafish. Danio rerio Brain Struct Funct. 2019;224(2):627–42.

    Article  CAS  PubMed  Google Scholar 

  77. Shim JW, Territo PR, Simpson S, Watson JC, Jiang L, Riley AA, et al. Hydrocephalus in a rat model of Meckel Gruber syndrome with a TMEM67 mutation. Sci Rep. 2019;9(1):1069.

    Article  PubMed  PubMed Central  Google Scholar 

  78. Doğanli C, Beck HC, Ribera AB, Oxvig C, Lykke-Hartmann K. α3Na+/K+-ATPase deficiency causes brain ventricle dilation and abrupt embryonic motility in zebrafish. J Biol Chem. 2013;288(13):8862–74.

    Article  PubMed  PubMed Central  Google Scholar 

  79. Hurd TW, Otto EA, Mishima E, Gee HY, Inoue H, Inazu M, et al. Mutation of the Mg2+ transporter SLC41A1 results in a nephronophthisis-like phenotype. J Am Soc Nephrol. 2013;24(6):967–77.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  80. Duy PQ, Rakic P, Alper SL, Butler WE, Walsh CA, Sestan N, et al. Brain ventricles as windows into brain development and disease. Neuron. 2022;110(1):12–5.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  81. Mcallister JP, Guerra MM, Ruiz LC, Jimenez AJ, Dominguez-Pinos D, Sival D, et al. Ventricular zone disruption in human neonates with intraventricular hemorrhage. J Neuropathol Exp Neurol. 2017;76(5):358–75.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  82. Rodríguez EM, Guerra MM, Vío K, González C, Ortloff A, Bátiz LF, et al. A cell junction pathology of neural stem cells leads to abnormal neurogenesis and hydrocephalus. Biol Res. 2012;45(3):231–42.

    Article  PubMed  Google Scholar 

  83. Ortega E, Muñoz RI, Luza N, Guerra F, Guerra M, Vio K, et al. The value of early and comprehensive diagnoses in a human fetus with hydrocephalus and progressive obliteration of the aqueduct of Sylvius: case report. BMC Neurol. 2016;16:45.

    Article  PubMed  PubMed Central  Google Scholar 

  84. Fame RM, Cortés-Campos C, Sive HL. Brain ventricular system and cerebrospinal fluid development and function: light at the end of the tube: a primer with latest insights. BioEssays. 2020;42(3):e1900186.

    Article  PubMed  Google Scholar 

  85. Guerra M. Neural stem cells: are they the hope of a better life for patients with fetal-onset hydrocephalus?. Fluids Barriers CNS. 2014;11:7.

    Article  PubMed  PubMed Central  Google Scholar 

  86. Sival DA, Guerra M, Den Dunnen WF, Bátiz LF, Alvial G, Castañeyra-Perdomo A, et al. Neuroependymal denudation is in progress in full-term human foetal spina bifida aperta. Brain Pathol. 2011;21(2):163–79.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  87. Deng S, Gan L, Liu C, Xu T, Zhou S, Guo Y, et al. Roles of ependymal cells in the physiology and pathology of the central nervous system. Aging Dis. 2023;14(2):468–83.

    PubMed  PubMed Central  Google Scholar 

  88. Guerra MM, Henzi R, Ortloff A, Lichtin N, Vío K, Jiménez AJ, et al. Cell junction pathology of neural stem cells is associated with ventricular zone disruption, hydrocephalus, and abnormal neurogenesis. J Neuropathol Exp Neurol. 2015;74(7):653–71.

    Article  PubMed  Google Scholar 

  89. Rodríguez EM, Guerra MM. Neural stem cells and fetal-onset hydrocephalus. Pediatr Neurosurg. 2017;52(6):446–61.

    Article  PubMed  Google Scholar 

  90. Rodríguez E, Guerra M. Physiopathology of foetal onset hydrocephalus. In: Limbrick D, Leonard J, editors. lifelong implications of cerebrospinal fluid disorders. Bern: Springer; 2019.

    Google Scholar 

  91. Bustamante FA, Miro MP, Vel Squez ZD, Molina L, Ehrenfeld P, Rivera FJ, et al. Role of adherens junctions and apical-basal polarity of neural stem/progenitor cells in the pathogenesis of neurodevelopmental disorders: a novel perspective on congenital Zika syndrome. Transl Res. 2019;210:57–79.

    Article  PubMed  Google Scholar 

  92. Henzi R, Vío K, Jara C, Johanson CE, Mcallister JP, Rodríguez EM, et al. Neural stem cell therapy of foetal onset hydrocephalus using the HTx rat as experimental model. Cell Tissue Res. 2020;381(1):141–61.

    Article  CAS  PubMed  Google Scholar 

  93. Wagner C, Batiz LF, Rodríguez S, Jiménez AJ, Páez P, Tomé M, et al. Cellular mechanisms involved in the stenosis and obliteration of the cerebral aqueduct of hyh mutant mice developing congenital hydrocephalus. J Neuropathol Exp Neurol. 2003;62(10):1019–40.

    Article  CAS  PubMed  Google Scholar 

  94. Naruse I, Keino H. Apoptosis in the developing CNS. Prog Neurobiol. 1995;47(2):135–55.

    Article  CAS  PubMed  Google Scholar 

  95. Zizioli D, Tiso N, Guglielmi A, Saraceno C, Busolin G, Giuliani R, et al. Knock-down of pantothenate kinase 2 severely affects the development of the nervous and vascular system in zebrafish, providing new insights into PKAN disease. Neurobiol Dis. 2016;85:35–48.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  96. Gonzalez AM, Podvin S, Lin SY, Miller MC, Botfield H, Leadbeater WE, et al. Ecrg4 expression and its product augurin in the choroid plexus: impact on fetal brain development, cerebrospinal fluid homeostasis and neuroprogenitor cell response to CNS injury. Fluids Barriers CNS. 2011;8(1):6.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  97. Mori N, Kuwamura M, Tanaka N, Hirano R, Nabe M, Ibuki M, et al. Ccdc85c encoding a protein at apical junctions of radial glia is disrupted in hemorrhagic hydrocephalus (hhy) mice. Am J Pathol. 2012;180(1):314–27.

    Article  CAS  PubMed  Google Scholar 

  98. Brugmans AK, Walter C, Moreno N, Göbel C, Holdhof D, De Faria FW, et al. A carboxy-terminal Smarcb1 point mutation induces hydrocephalus formation and affects AP-1 and neuronal signalling pathways in mice. Cell Mol Neurobiol. 2023;43(7):3511–26.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  99. Bardella C, Al-Dalahmah O, Krell D, Brazauskas P, Al-Qahtani K, Tomkova M, et al. Expression of Idh 1(R132H) in the murine subventricular zone stem cell niche recapitulates features of early gliomagenesis. Cancer Cell. 2016;30(4):578–94.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  100. Teng Y, Xie X, Walker S, Saxena M, Kozlowski DJ, Mumm JS, et al. Loss of zebrafish lgi1b leads to hydrocephalus and sensitization to pentylenetetrazol induced seizure-like behavior. PLoS One. 2011;6(9):e24596.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  101. Rodríguez EM, Rodríguez S, Hein S. The subcommissural organ. Microsc Res Tech. 1998;41(2):98–123.

    Article  PubMed  Google Scholar 

  102. Guiñazú MF, Richter HG, Rodríguez EM. Bovine floor plate explants secrete SCO-spondin. Cell Tissue Res. 2002;308(2):177–91.

    Article  PubMed  Google Scholar 

  103. Meiniel O, Meiniel R, Lalloué F, Didier R, Jauberteau MO, Meiniel A, et al. The lengthening of a giant protein: when, how, and why?. J Mol Evol. 2008;66(1):1–10.

    Article  CAS  PubMed  Google Scholar 

  104. Guerra MM, González C, Caprile T, Jara M, Vío K, Muñoz RI, et al. Understanding how the subcommissural organ and other periventricular secretory structures contribute via the cerebrospinal fluid to neurogenesis. Front Cell Neurosci. 2015;9:480.

    Article  PubMed  PubMed Central  Google Scholar 

  105. Yang S, Emelyanov A, You MS, Sin M, Korzh V. Camel regulates development of the brain ventricular system. Cell Tissue Res. 2021;383(2):835–52.

    Article  CAS  PubMed  Google Scholar 

  106. Pérez-Fígares JM, Jimenez AJ, Rodríguez EM. Subcommissural organ, cerebrospinal fluid circulation, and hydrocephalus. Microsc Res Tech. 2001;52(5):591–607.

    Article  PubMed  Google Scholar 

  107. Aboitiz F, Montiel JF. The enigmatic Reissner’s fiber and the origin of chordates. Front Neuroanat. 2021;15:703835.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  108. Ortloff AR, Vío K, Guerra M, Jaramillo K, Kaehne T, Jones H, et al. Role of the subcommissural organ in the pathogenesis of congenital hydrocephalus in the HTx rat. Cell Tissue Res. 2013;352(3):707–25.

    Article  CAS  PubMed  Google Scholar 

  109. Rodríguez EM, Oksche A, Montecinos H. Human subcommissural organ, with particular emphasis on its secretory activity during the fetal life. Microsc Res Tech. 2001;52(5):573–90.

    Article  PubMed  Google Scholar 

  110. Ramos C, Fernández-Llebrez P, Bach A, Robert B, Soriano E. Msx1 disruption leads to diencephalon defects and hydrocephalus. Dev Dyn. 2004;230(3):446–60.

    Article  CAS  PubMed  Google Scholar 

  111. Rajagopal A, Rao AU, Amigo J, Tian M, Upadhyay SK, Hall C, et al. Haem homeostasis is regulated by the conserved and concerted functions of HRG-1 proteins. Nature. 2008;453(7198):1127–31.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  112. Liu J, Fraser SD, Faloon PW, Rollins EL, Vom Berg J, Starovic-Subota O, et al. A betaPix Pak2a signaling pathway regulates cerebral vascular stability in zebrafish. Proc Natl Acad Sci U S A. 2007;104(35):13990–5.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  113. Martinez ME, Pinz I, Preda M, Norton CR, Gridley T, Hernandez A. DIO3 protects against thyrotoxicosis-derived cranio-encephalic and cardiac congenital abnormalities. JCI Insight. 2022;7(21):e161214.

    Article  PubMed  PubMed Central  Google Scholar 

  114. Wheway G, Abdelhamed Z, Natarajan S, Toomes C, Inglehearn C, Johnson CA. Aberrant Wnt signalling and cellular over-proliferation in a novel mouse model of Meckel-Gruber syndrome. Dev Biol. 2013;377(1):55–66.

    Article  CAS  PubMed  Google Scholar 

  115. Yang L, Zeng C, Zhang Y, Wang F, Takamiya M, Strähle U. Functions of thioredoxin1 in brain development and in response to environmental chemicals in zebrafish embryos. Toxicol Lett. 2019;314:43–52.

    Article  CAS  PubMed  Google Scholar 

  116. Lolansen SD, Rostgaard N, Oernbo EK, Juhler M, Simonsen AH, Macaulay N. Inflammatory markers in cerebrospinal fluid from patients with hydrocephalus: a systematic literature review. Dis Markers. 2021;2021:8834822.

    Article  PubMed  PubMed Central  Google Scholar 

  117. Hale AT, Bastarache L, Morales DM, Wellons JC 3rd, Limbrick DD Jr, Gamazon ER. Multi-omic analysis elucidates the genetic basis of hydrocephalus. Cell Rep. 2021;35(5):109085.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  118. Day JW, Finkel RS, Chiriboga CA, Connolly AM, Crawford TO, Darras BT, et al. Onasemnogene abeparvovec gene therapy for symptomatic infantile-onset spinal muscular atrophy in patients with two copies of SMN2 (STR1VE): an open-label, single-arm, multicentre, phase 3 trial. Lancet Neurol. 2021;20(4):284–93.

    Article  CAS  PubMed  Google Scholar 

  119. Hu ML, Edwards TL, Ohare F, Hickey DG, Wang JH, Liu Z, et al. Gene therapy for inherited retinal diseases: progress and possibilities. Clin Exp Optom. 2021;104(4):444–54.

    Article  PubMed  Google Scholar 

  120. Amado DA, Davidson BL. Gene therapy for ALS: a review. Mol Ther. 2021;29(12):3345–58.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  121. Blazer-Yost BL. Consideration of kinase inhibitors for the treatment of hydrocephalus. Int J Mol Sci. 2023;24(7):6673.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  122. Zhang K, Gao M, Wang G, Shi Y, Li X, Lv Y, et al. Hydrocephalus in cblC type methylmalonic acidemia. Metab Brain Dis. 2019;34(2):451–8.

    Article  CAS  PubMed  Google Scholar 

  123. Rijken BF, Lequin MH, Van Veelen ML, De Rooi J, Mathijssen IM. The formation of the foramen magnum and its role in developing ventriculomegaly and Chiari I malformation in children with craniosynostosis syndromes. J Craniomaxillofac Surg. 2015;43(7):1042–8.

    Article  PubMed  Google Scholar 

  124. Finsterer J, Zarrouk-Mahjoub S. Phenotypic spectrum of SLC25A4 mutations. Biomed Rep. 2018;9(2):119–22.

    CAS  PubMed  PubMed Central  Google Scholar 

Download references

Acknowledgements

The authors thank Figdraw (www.figdraw.com) because part of the figures was created by it.

Funding

This study was funded by the National Key R&D Program of China (2021YFF1200602).

Author information

Authors and Affiliations

Authors

Contributions

XYL and DM participated in the design and conception of the study. MJP and XS prepares and crated the initial draft. MC, CR, ZC, JLS, HJY, GYG, PS and FG reviewed and revised the draft. All authors read and approved the final manuscript.

Corresponding authors

Correspondence to Mei-Jun Pang or Dong Ming.

Ethics declarations

Ethics approval and consent to participate

Not applicable.

Consent for publication

Not applicable.

Competing interests

The authors declare that they have no competing interests.

Rights and permissions

Open Access This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if changes were made. The images or other third party material in this article are included in the article's Creative Commons licence, unless indicated otherwise in a credit line to the material. If material is not included in the article's Creative Commons licence and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this licence, visit http://creativecommons.org/licenses/by/4.0/. The Creative Commons Public Domain Dedication waiver (http://creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated in a credit line to the data.

Reprints and permissions

About this article

Check for updates. Verify currency and authenticity via CrossMark

Cite this article

Liu, XY., Song, X., Czosnyka, M. et al. Congenital hydrocephalus: a review of recent advances in genetic etiology and molecular mechanisms. Military Med Res 11, 54 (2024). https://doi.org/10.1186/s40779-024-00560-5

Download citation

  • Received:

  • Accepted:

  • Published:

  • DOI: https://doi.org/10.1186/s40779-024-00560-5

Keywords