Evc is essential for Indian Hedgehog (Hh) signalling in the cartilage growth plate. The gene encoding Evc2 is in close proximity in divergent orientation to Evc and mutations in both human genes lead to the chondrodysplasia Ellis-van Creveld syndrome.
Bioinformatic analysis reveals that the Evc and Evc2 genes arose through a duplication event early in metazoan evolution and were subsequently lost in arthropods and nematodes. Here we demonstrate that Evc2 is essential for Hh pathway activation in response to the Smo agonist purmorphamine. A yeast two-hybrid screen using Evc as bait identified Evc2 as an Evc binding partner and we confirmed the interaction by immunoprecipitation. We developed anti-Evc2 antibodies and show that Evc2 and Evc co-localize at the basal body and also on primary cilia. In transfected cells, basal body and cilia localization is observed when Evc and Evc2 constructs are co-transfected but not when either construct is transfected individually. We show that Evc and Evc2 are cilia transmembrane proteins, the C-terminus for both being intracellular and Evc2, but not Evc, having an extracellular portion. Furthermore, Evc is absent at the basal body in Evc2 null cells. Using Western blots of cytoplasmic and nuclear protein, we also demonstrate that full length Evc2 but not Evc, is located in the nucleus.
We demonstrate for the first time that Evc2 is a positive regulator of the Hh signalling pathway and that it is located at the basal body of primary cilia. We show that the presence of Evc and Evc2 at the basal body and cilia membrane is co-dependent. In addition, Evc2, but not Evc, is present in the cell nucleus suggesting movement of Evc2 between the cilium and nucleus.
Background. Ellis-van Creveld (EvC) syndrome is a rare, autosomal recessive disorder characterized by short stature, short limbs, growth retardation, polydactyly, and ectodermal defects with cardiac anomalies occurring in around 60% of cases. EVC syndrome has been linked to mutations in EVC and EVC2 genes. Case Presentation. We report EvC syndrome in two unrelated Lebanese families both having homozygous mutations in the EVC2 gene, c.2653C>T (p.(Arg885*)) and c.2012_2015del (p.(Leu671*)) in exons 15 and 13, respectively, with the latter being reported for the first time. Conclusion. Although EvC has been largely described in the medical literature, clinical features of this syndrome vary. While more research is required to explore other genes involved in EvC, early diagnosis and therapeutic care are important to achieve a better quality of life.
Ellis-van Creveld (EvC) syndrome is characterized by short limbs, short ribs, postaxial polydactyly, dysplastic nails and teeth and is inherited in an autosomal recessive pattern. We report a family with complex septal cardiac defects, rhizomelic limb shortening, and polydactyly, without the typical lip, dental, and nail abnormalities of EvC. The phenotype was inherited in an autosomal recessive pattern, with one instance of pseudodominant inheritance.
Because of the phenotypic overlap with EvC, microsatellite markers were used to test for linkage to the EVC/EVC2 locus. The results did not exclude linkage, so samples were sequenced for mutations.
We identified a c.1868T>C mutation in EVC, which predicts p.L623P, and was homozygous in affected individuals.
We conclude that this EVC mutation is hypomorphic and that such mutations can cause a phenotype of cardiac and limb defects that is less severe than typical EvC. EVC mutation analysis should be considered in patients with cardiac and limb malformations, even if they do not manifest typical EvC syndrome.
Ellis-van Creveld (EvC) syndrome is a rare autosomal recessive malformation syndrome with the main features cardiac defects, postaxial hexadactyly, mesomelic shortening of the limbs, short ribs, dysplastic nails and teeth, oral frenula and various other abnormalities while mental function is normal. We describe 2 adult EvC patients with the cardinal skeletal features of mesomelic short stature and severe, progressive genu valgum deformity, resulting from loss of function mutations in the EVC genes. While the genu valgum was the predominating and disabling feature in patient 1, patient 2 showed acroosteolyses in the distal phalanges and a symmetrical synostosis of metacarpals in his hands. Moreover, patient 2 developed synostoses in the additional fingers in adolescence which had not been present at the age of 12 years, suggesting a further progression of skeletal disease. Joint fusion of phalanges so far has not been reported in EvC syndrome. Our data further expand the phenotypic spectrum of EvC related skeletal malformations and contribute important new information on the clinical course of EvC syndrome with increasing age.
Ellis-van Creveld syndrome; EVC genes; Genu valgum; Skeletal manifestation; Treatment
During the summer of 2013 seven Italian Tyrolean Grey calves were born with abnormally short limbs. Detailed clinical and pathological examination revealed similarities to chondrodysplastic dwarfism. Pedigree analysis showed a common founder, assuming autosomal monogenic recessive transmission of the defective allele. A positional cloning approach combining genome wide association and homozygosity mapping identified a single 1.6 Mb genomic region on BTA 6 that was associated with the disease. Whole genome re-sequencing of an affected calf revealed a single candidate causal mutation in the Ellis van Creveld syndrome 2 (EVC2) gene. This gene is known to be associated with chondrodysplastic dwarfism in Japanese Brown cattle, and dwarfism, abnormal nails and teeth, and dysostosis in humans with Ellis-van Creveld syndrome. Sanger sequencing confirmed the presence of a 2 bp deletion in exon 19 (c.2993_2994ACdel) that led to a premature stop codon in the coding sequence of bovine EVC2, and was concordant with the recessive pattern of inheritance in affected and carrier animals. This loss of function mutation confirms the important role of EVC2 in bone development. Genetic testing can now be used to eliminate this form of chondrodysplastic dwarfism from Tyrolean Grey cattle.
Hedgehog (Hh) signaling plays pivotal roles in embryonic development and adult tissue homeostasis in species ranging from Drosophila to mammals. The Hh signal is transduced by Smoothened (Smo), a seven-transmembrane protein related to G protein coupled receptors. Despite a conserved mechanism by which Hh activates Smo in Drosophila and mammals, how mammalian Hh signal is transduced from Smo to the Gli transcription factors is poorly understood. Here, we provide evidence that two ciliary proteins, Evc and Evc2, the products of human disease genes responsible for the Ellis-van Creveld syndrome, act downstream of Smo to transduce the Hh signal. We found that loss of Evc/Evc2 does not affect Sonic Hedgehog-induced Smo phosphorylation and ciliary localization but impedes Hh pathway activation mediated by constitutively active forms of Smo. Evc/Evc2 are dispensable for the constitutive Gli activity in Sufu−/− cells, suggesting that Evc/Evc2 act upstream of Sufu to promote Gli activation. Furthermore, we demonstrated that Hh stimulates binding of Evc/Evc2 to Smo depending on phosphorylation of the Smo C-terminal intracellular tail and that the binding is abolished in Kif3a−/− cilium-deficient cells. We propose that Hh activates Smo by inducing its phosphorylation, which recruits Evc/Evc2 to activate Gli proteins by antagonizing Sufu in the primary cilia.
Evc; Evc2; Hedgehog; Smo; Gli
Hypospadias has a complex etiology with both genetic and environmental factors contributing to the condition. Urogenital abnormalities including hypospadias, are found in 22% of cases with Ellis van Creveld syndrome (EvC). Mutations in the EVC gene can cause major and minor anomalies, which form phenotypes that partially overlap with those present in EvC.
The aim of this study was to evaluate the association between nucleotide variants of the EVC gene and the risk of hypospadias.
Material and methods
Four single nucleotide polymorphisms (SNPs) of the EVC gene (rs3774856, rs2302075, rs1383180, rs7680768) were taken under investigation in 96 patients with isolated hypospadias and 284 matched controls. Genotyping of all polymorphisms was carried out by PCR and followed by appropriate restriction enzyme digestion (PCR-RFLP).
Individuals homozygous for the SNP rs2302075 (p.Thr449Lys) showed an elevated risk for hypospadias. Haplotypes containing the rs2302075 variant also revealed modest associations with hypospadias, which did not survive multiple testing corrections. None of the other tested EVC polymorphisms displayed significant association with the risk of hypospadias, either in dominant or recessive inheritance models.
The results of this study suggest that polymorphic variants of the EVC gene do not substantially contribute to the risk of hypospadias based on our study population. However, further studies should help to clarify the relationship between polymorphisms of EVC and hypospadias.
hypospadias; Ellis-van Creveld syndrome; gene polymorphisms
Ellis-van Creveld syndrome (EVC) is a chondral and ectodermal dysplasia characterized by short ribs, polydactyly, growth retardation, and ectodermal and heart defects. It is a rare disease with approximately 150 cases reported worldwide. The exact prevalence is unknown, but the syndrome seems more common among the Amish community. Prenatal abnormalities (that may be detected by ultrasound examination) include narrow thorax, shortening of long bones, hexadactyly and cardiac defects. After birth, cardinal features are short stature, short ribs, polydactyly, and dysplastic fingernails and teeth. Heart defects, especially abnormalities of atrial septation, occur in about 60% of cases. Cognitive and motor development is normal. This rare condition is inherited as an autosomal recessive trait with variable expression. Mutations of the EVC1 and EVC2 genes, located in a head to head configuration on chromosome 4p16, have been identified as causative. EVC belongs to the short rib-polydactyly group (SRP) and these SRPs, especially type III (Verma-Naumoff syndrome), are discussed in the prenatal differential diagnosis. Postnatally, the essential differential diagnoses include Jeune dystrophy, McKusick-Kaufman syndrome and Weyers syndrome. The management of EVC is multidisciplinary. Management during the neonatal period is mostly symptomatic, involving treatment of the respiratory distress due to narrow chest and heart failure. Orthopedic follow-up is required to manage the bones deformities. Professional dental care should be considered for management of the oral manifestations. Prognosis is linked to the respiratory difficulties in the first months of life due to thoracic narrowness and possible heart defects. Prognosis of the final body height is difficult to predict.
The Hedgehog (Hh) pathway depends on primary cilia in vertebrates, but the signaling machinery within cilia remains incompletely defined. We report the identification of a complex between two ciliary proteins, EFCAB7 and IQCE, which positively regulates the Hh pathway. The EFCAB7-IQCE module anchors the EVC-EVC2 complex in a signaling microdomain at the base of cilia. EVC and EVC2 genes are mutated in Ellis van Creveld and Weyers syndromes, characterized by impaired Hh signaling in skeletal, cardiac and orofacial tissues. EFCAB7 binds to a C-terminal disordered region in EVC2 that is deleted in Weyers patients. EFCAB7 depletion mimics the Weyers cellular phenotype— the mis-localization of EVC-EVC2 within cilia and impaired activation of the transcription factor GLI2. Evolutionary analysis suggests that emergence of these complexes might have been important for adaptation of an ancient organelle, the cilium, for an animal-specific signaling network.
Ellis–van Creveld (EvC) syndrome is a congenital malformation syndrome with marked growth retardation. In this study, specific growth charts for EvC patients were derived to allow better follow-up of growth and earlier detection of growth patterns unusual for EvC. With the use of 235 observations of 101 EvC patients (49 males, 52 females), growth charts for males and females from 0 to 20 years of age were derived. Longitudinal and cross-sectional data were collected from an earlier review of growth data in EvC, a database of EvC patients, and from recent literature. To model the growth charts, the GAMLSS package for the R statistical program was used. Height of EvC patients was compared to healthy children using Dutch growth charts. Data are presented both on a scale for age and on a scale for the square root of age. Compared to healthy Dutch children, mean height standard deviation score values for male and female EvC patients were −3.1 and −3.0, respectively. The present growth charts should be useful in the follow-up of EvC patients. Most importantly, early detection of growth hormone deficiency, known to occur in EvC, will be facilitated.
Growth; Body height; Ellis–van Creveld syndrome; Growth charts
Ellis-van Creveld (EVC) syndrome is a genetic disorder with autosomal recessive transmission, which may clinically present as small stature, short limbs, fine sparse hair, hypoplastic fingernails, multiple musculofibrous frenula, conical teeth, hypoplasia of the enamel, hypodontia, and malocclusion. Heart defects, especially abnormalities of atrial septation, have been found in about 60% of cases. The mutation in EVC and EVC2 gene is responsible for this syndrome. The presence of multiple orodental findings makes this syndrome important for dentists. The aim of this article is to present a rare case of EVC syndrome in a 10-year-old girl along with the review of literature.
Chondroectodermal dysplasia; Ellis-van Creveld syndrome; polydactyly
Ellis-van Creveld syndrome is a rare short-limbed disproportionate dwarfism characterized by postaxial polydactyly, several skeletal, oral mucosal and dental anomalies, nail dysplasia and in 50-60% cases of congenital cardiac defects. It is an autosomal recessive disorder with mutations of the EVC1 and EVC2 genes located on chromosome 4p16. Patients with this syndrome usually have a high mortality in early life due to cardiorespiratory problems. We present the case of a six- month-old female infant with Ellis-van Creveld syndrome - essential infantile esotropia, which has been infrequently documented in the literature.
Postaxial polydactyly; disproportionate dwarfism; hypoplastic nails; essential infantile esotropia
Ellis–van Creveld syndrome (EvC) is a rare autosomal recessive chondroectodermal dysplasia, associated with mutations in the EVC1 and EVC2 genes (4p16). The management of EvC is multidisciplinary, and early diagnosis is of the utmost importance for efficient and timely treatment. The main prognostic determinant is presence of a heart defect. The authors describe the case of a 42-year-old man referred to our outpatient cardiology clinic, following surgical repair of an atrial septal defect. He had presented to different medical specialties on numerous occasions since childhood, but remained without a clear diagnosis for more than 40 years. This case reinforces the need for a holistic view when assessing a patient with congenital heart disease. Moreover, this illustrates the importance of communication and discussion between different medical specialties.
Mutations identified in a cohort of patients with atrioventricular septal defects as a part of Ellis van Creveld syndrome (EvC syndrome) led us to study the role of two non-homologous genes, EVC and LBN, in heart development and disease pathogenesis. To address the cause of locus heterogeneity resulting in an indistinguishable heart–hand phenotype, we carried out in situ hybridization and immunofluorescence and identified co-localization of Evc and Lbn mRNA and protein. In the heart, expression was identified to be strongest in the secondary heart field, including both the outflow tract and the dorsal mesenchymal protrusion, but was also found in mesenchymal structures of the atrial septum and the atrioventricular cushions. Finally, we studied the transcriptional hierarchy of EVC and LBN but did not find any evidence of direct transcriptional interregulation between the two. Due to the locus heterogeneity of human mutations predicted to result in a loss of protein function, a bidirectional genomic organization and overlapping expression patterns, we speculate that these proteins function coordinately in cardiac development and that loss of this coordinate function results in the characteristics of EvC syndrome.
One of the hallmarks of cancer, global gene expression alteration, is closely associated with the development and malignant characteristics associated with adult T-cell leukemia (ATL) as well as other cancers. Here, we show that aberrant overexpression of the Ellis Van Creveld (EVC) family is responsible for cellular Hedgehog (HH) activation, which provides the pro-survival ability of ATL cells. Using microarray, quantitative RT-PCR and immunohistochemistry we have demonstrated that EVC is significantly upregulated in ATL and human T-cell leukemia virus type I (HTLV-1)-infected cells. Epigenetic marks, including histone H3 acetylation and Lys4 trimethylation, are specifically accumulated at the EVC locus in ATL samples. The HTLV-1 Tax participates in the coordination of EVC expression in an epigenetic fashion. The treatment of shRNA targeting EVC, as well as the transcription factors for HH signaling, diminishes the HH activation and leads to apoptotic death in ATL cell lines. We also showed that a HH signaling inhibitor, GANT61, induces strong apoptosis in the established ATL cell lines and patient-derived primary ATL cells. Therefore, our data indicate that HH activation is involved in the regulation of leukemic cell survival. The epigenetically deregulated EVC appears to play an important role for HH activation. The possible use of EVC as a specific cell marker and a novel drug target for HTLV-1-infected T-cells is implicated by these findings. The HH inhibitors are suggested as drug candidates for ATL therapy. Our findings also suggest chromatin rearrangement associated with active histone markers in ATL.
ATL; epigenetics; EVC; Hedgehog; HTLV-1
Ellis Van Creveld syndrome (EVC), also known as chondroectodermal dysplasia, presents at birth with short limbs accompanied by postaxial polydactyly, nail dysplasia, and dental anomalies. Other manifestations of EVC include atrial septum defects and other congenital heart diseases. We report a case of the EVC syndrome with postaxial polydactyly (Synpolydactyly with seven fingers on the right side and hexadactyly on the left side) and a partial atrioventricular canal defect diagnosed antenatally. This variation of EVS has not been reported in English literature till date.
Antenatal diagnosis; cardiac malformation; ellis van creveld syndrome; synpolydactyly; ultrasonography
Meckel–Gruber syndrome (MKS, OMIM #249000) is a multiple congenital malformation syndrome that represents the severe end of the ciliopathy phenotypic spectrum. Despite the relatively common occurrence of this syndrome among Arabs, little is known about its genetic architecture in this population. This is a series of 18 Arab families with MKS, who were evaluated clinically and studied using autozygome-guided mutation analysis and exome sequencing. We show that autozygome-guided candidate gene analysis identified the underlying mutation in the majority (n=12, 71%). Exome sequencing revealed a likely pathogenic mutation in three novel candidate MKS disease genes. These include C5orf42, Ellis–van-Creveld disease gene EVC2 and SEC8 (also known as EXOC4), which encodes an exocyst protein with an established role in ciliogenesis. This is the largest and most comprehensive genomic study on MKS in Arabs and the results, in addition to revealing genetic and allelic heterogeneity, suggest that previously reported disease genes and the novel candidates uncovered by this study account for the overwhelming majority of MKS patients in our population.
autozygome; ciliopathy; encephalocele; EVC2; EXOC4
Ellis-van Creveld (EvC) syndrome is a rare autosomal recessive malformation disorder. Cardiac defects are observed in about 50% of EvC cases. Surgical data is lacking on the prognosis and life expectancy of EvC patients. Herein, we report the case of a 38-year-old man with EvC syndrome who underwent two surgical corrections for cardiac anomalies. This report supplements the available information on the clinical course of EvC syndrome in older patients.
adulthood; Ellis-van Creveld syndrome; mitral regurgitation
Ellis van Creveld syndrome (EVCS) is mainly characterized by dysplatic changes in skeletal structures along with variable inter- and intra-familial patterns. Shortening of bony structures such as ribs and limbs, postaxial polydactyly, and dysplastic teeth and nails are among the clinical presentation of this autosomal recessive disease.
Epidermoid cyst; Enucleation; Impacted wisdom teeth; Mandible
Ellis-van Creveld (EvC) syndrome or chondroectodermal dysplasia is an autosomal recessive disorder with characteristic clinical manifestations. The four principal characteristics are chondrodysplasia, polydactyly, ectodermal dysplasia and congenital heart defects. Its incidence in the general population is low. The oral manifestations of EvC syndrome include both soft tissues and teeth, but the dental literature on the subject is scarce. The present case describes the constant and variable oral findings in these patients, which can be diagnosed at any age, even during pregnancy. The presence of a variety of oral manifestations, such as fusion of upper lip to the gingival margin, presence of multiple frenula, abnormally shaped and microdontic teeth and congenitally missing teeth requires multidisciplinary dental treatment, with consideration for the high incidence of cardiac defects in these patients.
Ellis–van Creveld syndrome (EVC) is an autosomal recessive disorder characterized by chondrodystrophy, polydactyly, ectodermal dysplasia, and cardiac anomalies. Acromelic shortening of upper and lower limbs, genu valgum, multiple frenula, deformed teeth, short ribs and narrow thorax and congenital heart diseases complete the picture. The patients with the syndrome rarely survive into adulthood. Here, we report a lady with EVC presenting for the first time in middle age.
Ellis–van Creveld syndrome; Ciliopathy; Short rib narrow thorax syndromes
Ellis Van Creveld syndrome (EVC) is a rare genetic disorder having autosomal recessive inheritance affecting the Amish population of Pennsylvania in USA with incidence of 1:244,000 for the general population. This syndrome consists of characteristic features such as bilateral postaxial polydactyly, chondroectodermal dysplasia, congenital heart defects and hypoplastic nails and teeth. There are few case reports of this syndrome reported in dental literature. We report a case of a 17 year old female presenting typical features of this syndrome and the oral findings of this patient which are the key diagnostic features.
Ellis Van Creveld syndrome; Polydactyly; Chondroectodermal dysplasia
Skeletal dysplasias are a heterogenous group of disorders combining abnormalities in the skull and other skeletal bones. Weyers acrofacial dysostosis also known as Weyers acrodental dysostosis was first described in 1952, by Weyers, as a postaxial polydactyly, which had features distinct from, yet some in common with the Ellis-van Creveld Syndrome (EvC). Both the syndromes have been mapped to the same chromosome, 4p16. The cases reported here highlight the overlapping features of both syndromes, which are dissimilar in mode of inheritance and phenotypic severity, emphasizing the need for genetic analysis, to categorize these conditions.
Ellis-van Creveld; polydactyly; syndrome; weyers acrodental dysostosis
Ellis–van Creveld (EVC) syndrome is an autosomal recessive disorder that is also known as chondro-ectodermal dysplasia. The common manifestations of this syndrome are short ribs, postaxial polydactyly, growth retardation, and ectodermal and cardiac defects. The present case report is about an 8-year-old boy who had the features of bilateral hexadactyly, knocked knees, cardiac problems, congenital absence of incisors, fused upper and lower labial frenulum, and mulberry molars.
Abnormal frenal attachments; chondro-ectodermal dysplasia; Ellis–van Creveld syndrome; mulberry molars; polydactyly
Orodental anomalies are one aspect of rare diseases and are increasingly identified as diagnostic and predictive traits. To understand the rationale behind gene expression during tooth or other ectodermal derivative development and the disruption of odontogenesis or hair and salivary gland formation in human syndromes we analyzed the expression patterns of a set of genes (Irf6, Nfkbia, Ercc3, Evc2, Map2k1) involved in human ectodermal dysplasias in mouse by in situ hybridization. The expression patterns of Nfkbia, Ercc3 and Evc2 during odontogenesis had never been reported previously. All genes were indeed transcribed in different tissues/organs of ectodermal origin. However, for Nfkbia, Ercc3, Evc2, and Map2k1, signals were also present in the ectomesenchymal components of the tooth germs. These expression patterns were consistent in timing and localization with the known dental anomalies (tooth agenesis, microdontia, conical shape, enamel hypoplasia) encountered in syndromes resulting from mutations in those genes. They could also explain the similar orodental anomalies encountered in some of the corresponding mutant mouse models. Translational approaches in development and medicine are relevant to gain understanding of the molecular events underlying clinical manifestations.
Dental anomalies; Ectodermal dysplasia; Gene expression; Mouse; Tooth development