Ellis-van Creveld syndrome: A rare clinical entity

Caroli syndrome associated with atrial septal defect and polydactyly: a case report

INTRODUCTION

Caroli disease is multifocal segmental dilatation of the large intrahepatic bile ducts that connect to the main duct. It is considered a rare disease with an incidence rate of 1 in 1,000,000 births. There are two types of Caroli: the first type is the simple type, Caroli disease, which includes only cystic dilatation of the intrahepatic bile ducts. The second is called Caroli syndrome, which consists of Caroli disease and congenital hepatic fibrosis and might lead to portal hypertension leading to esophageal varices and splenomegaly. Atrial septal defect is one of the most common congenital heart diseases, occurring when the connection between the left and the right atriums fails to close. Polydactyly is one of the most common congenital malformations of the hands and feet. It manifests in excess fingers on the hands or toes.

CASE PRESENTATION

A 6-year-old Arab girl presented to the hospital with abdominal pain for the last month with abdominal enlargement. The patient was already diagnosed with Caroli disease and polydactyly (six fingers on each limb) when she was born. Investigations including complete blood count, blood smear, bone marrow biopsy, esophagoscopy, abdominal ultrasound, and computed tomography scan showed splenomegaly associated with hypersplenism, fourth-grade non-bleeding varices, intrahepatic cystic formations in the left and right lobes, and an atrial septal defect with a left-to-right shunt. The patient was scheduled for a splenectomy after she was vaccinated with the appropriate vaccines. After follow-up for a week in the hospital, complete blood count showed an improvement. A month after that, the patient had liver abscesses and biliary fistula that were treated appropriately and her symptoms resolved.

CONCLUSION

The association of liver diseases, polydactyly, and congenital heart diseases is extremely rare and was only documented few times in the literature. However, to our knowledge, atrial septal defect has never been part of this combination before. The family history also makes this case unique and strongly suggests genetic etiology.

Primary Cilia and Their Role in Acquired Heart Disease

Primary cilia are non-motile plasma membrane extrusions that display a variety of receptors and mechanosensors. Loss of function results in ciliopathies, which have been strongly linked with congenital heart disease, as well as abnormal development and function of most organ systems. Adults with congenital heart disease have high rates of acquired heart failure, and usually die from a cardiac cause. Here we explore primary cilia’s role in acquired heart disease. Intraflagellar Transport 88 knockout results in reduced primary cilia, and knockout from cardiac endothelium produces myxomatous degeneration similar to mitral valve prolapse seen in adult humans. Induced primary cilia inactivation by other mechanisms also produces excess myocardial hypertrophy and altered scar architecture after ischemic injury, as well as hypertension due to a lack of vascular endothelial nitric oxide synthase activation and the resultant left ventricular dysfunction. Finally, primary cilia have cell-to-cell transmission capacity which, when blocked, leads to progressive left ventricular hypertrophy and heart failure, though this mechanism has not been fully established. Further research is still needed to understand primary cilia’s role in adult cardiac pathology, especially heart failure.

Role of primary cilia and Hedgehog signaling in craniofacial features of Ellis-van Creveld syndrome

Ellis-van Creveld syndrome (EvC) is an autosomal recessive genetic disorder involving pathogenic variants of EVC and EVC2 genes and classified as a ciliopathy. The syndrome is caused by mutations in the EVC gene on chromosome 4p16, and EVC2 gene, located close to the EVC gene, in a head-to-head configuration. Regardless of the affliction of EVC or EVC2, the clinical features of Ellis-van Creveld syndrome are similar. Both these genes are expressed in tissues such as, but not limited to, the heart, liver, skeletal muscle, and placenta, while the predominant expression in the craniofacial tissues is that of EVC2. Biallelic mutations of EVC and EVC2 affect Hedgehog signaling and thereby ciliary function, crucial factors in vertebrate development, culminating in the phenotypical features characteristic of EvC. The clinical features of Ellis-van Creveld syndrome are consistent with significant abnormalities in morphogenesis and differentiation of the affected tissues. The robust role of primary cilia in histodifferentiation and morphodifferentiation of oral, perioral, and craniofacial tissues is becoming more evident in the most recent literature. In this review, we give a summary of the mechanistic role of primary cilia in craniofacial development, taking Ellis-van Creveld syndrome as a representative example.

Oro-facial-digital syndrome type I: a case report with novel features

Oro-facial-digital syndrome is a group of rare heterogeneous hereditary disorders characterized by abnormalities of the oral cavity, face and digits, along with varying degrees of mental retardation. Currently, Oro-facial-digital syndrome has been classified into 14 types and two additional unclassified variants have been proposed. Amongst the various variants described, Oro-facial-digital syndrome type I is the most common. We report an interesting subclinical sporadic case of Oro-facial-digital syndrome type I in a 21-year-old female patient. Interestingly, our patient presented with a few novel hitherto unreported clinical findings like midline pits in the philtrum area and a hamartomatous proliferation of tissue in the anterior maxillary alveolar gingival region. This case report highlights the importance of prudent histopathological-clinical correlation, which can direct the flow of clinical investigations leading to the detection and diagnosis of unsuspected conditions as learned in this case. We would also like to emphasize that comprehensive examination of new born for structural abnormalities of the orofacial region is crucial to early diagnosis of syndromes and subsequent referral for further evaluation and management.

Oral manifestations in Ellis-van Creveld syndrome: a case report

Introduction: Ellis-van Creveld (EVC) syndrome is an uncommon genetic disease that can be diagnosed at any age. Observation: A case of EVC syndrome was reported in a young 3-year-old female patient presenting chondroectodermal dysplasia, polydactyly, congenital heart defects, damage to the oral mucosa and numerous dental alterations (number, form and structure). Oral management consists of teaching oral hygiene and the prophylactic filling of dental cracks. Discussion: EVC is an autosomal recessive disease. Its diagnosis is only based on clinical features and genetic studies. Conclusion: Dentists should be aware of this syndrome to avoid a late diagnosis and to facilitate a multidisciplinary management.

Ellis-van Creveld Syndrome: A Rare Clinical Report of Oral Rehabilitation by Interdisciplinary Approach

Ellis-van Creveld syndrome (EVC) is a very rare genetic disorder that affects various tissues of ectodermal and mesodermal origin; patients with EVC present with typical oral deficiencies. The affected individuals are quite young at the time of oral evaluation. It is, therefore, important that these individuals are diagnosed and receive dental treatment at an early age for their physiologic and psychosocial well-being. Albeit there are numerous articles penned on the EVC, the treatise from an oral perspective is inadequate, covering only oral exhibitions and the preventive treatments. This article reviews the literature and serves as the first disquisition for oral rehabilitation of an EVC patient utilizing surgical, orthodontic, restorative, and prosthodontic management.

Genome-Wide Association Study of Meiotic Recombination Phenotypes

Meiotic recombination is an essential step in gametogenesis, and is one that also generates genetic diversity. Genome-wide association studies (GWAS) and molecular studies have identified genes that influence of human meiotic recombination. RNF212 is associated with total or average number of recombination events, and PRDM9 is associated with the locations of hotspots, or sequences where crossing over appears to cluster. In addition, a common inversion on chromosome 17 is strongly associated with recombination. Other genes have been identified by GWAS, but those results have not been replicated. In this study, using new datasets, we characterized additional recombination phenotypes to uncover novel candidates and further dissect the role of already known loci. We used three datasets totaling 1562 two-generation families, including 3108 parents with 4304 children. We estimated five different recombination phenotypes including two novel phenotypes (average recombination counts within recombination hotspots and outside of hotspots) using dense SNP array genotype data. We then performed gender-specific and combined-sex genome-wide association studies (GWAS) meta-analyses. We replicated associations for several previously reported recombination genes, including RNF212 and PRDM9. By looking specifically at recombination events outside of hotspots, we showed for the first time that PRDM9 has different effects in males and females. We identified several new candidate loci, particularly for recombination events outside of hotspots. These include regions near the genes SPINK6, EVC2, ARHGAP25, and DLGAP2. This study expands our understanding of human meiotic recombination by characterizing additional features that vary across individuals, and identifying regulatory variants influencing the numbers and locations of recombination events.

Oral and craniofacial manifestations of Ellis-van Creveld syndrome: Case series

PURPOSE

The objective of this case series was to determine the oral, dental and craniofacial features of patients with EvC syndrome.

MATERIAL AND METHODS

Eight patients with EvC syndrome were enrolled. A complete family history, pedigree analysis, detailed medical history were collected. Findings of clinical examination, including craniofacial and orodental manifestations, and radiological investigations were thoroughly studied.

RESULTS

All eight patients had characteristic face, hypertrophic frenulum, conical and peg-shaped teeth, hypodontia of deciduous and/or permanent teeth and also skeletal dysplasia, small chest, short stature and hypoplastic nails. Additionally dysmorphic filtrum, serrated appearance of gingiva, diastema, enamel hypoplasia, microdontia, taurodontism, single rooted permanent molar, delayed eruption and high caries rate were observed with varying degrees. Cephalometric evaluation revealed skeletal Class III growth pattern in four subjects and Class II growth pattern in one subject.

CONCLUSION

Evaluation of craniofacial and orodental anomalies of EvC syndrome is required for accurate differential diagnosis from other congenital syndromes.

Novel mutations in EVC cause aberrant splicing in Ellis-van Creveld syndrome

Ellis-van Creveld syndrome (EvC) is a rare autosomal recessive disorder characterized by disproportionate chondrodysplasia, postaxial polydactyly, nail dystrophy, dental abnormalities and in a proportion of patients, congenital cardiac malformations. Weyers acrofacial dysostosis (Weyers) is another dominantly inherited disorder allelic to EvC syndrome but with milder phenotypes. Both disorders can result from loss-of-function mutations in either EVC or EVC2 gene, and phenotypes associated with the two gene mutations are clinically indistinguishable. We present here a clinical and molecular analysis of a Chinese family manifested specific features of EvC syndrome. Sequencing of both EVC and EVC2 identified two novel heterozygous splice site mutations c.384+5G>C in intron 3 and c.1465-1G>A in intron 10 in EVC, which were inherited from mother and father, respectively. In vitro minigene expression assay, RT-PCR and sequencing analysis demonstrated that c.384+5G>C mutation abolished normal splice site and created a new cryptic acceptor site within exon 4, whereas c.1465-1G>A mutation affected consensus splice junction site and resulted in full exon 11 skipping. These two aberrant pre-mRNA splicing processes both produced in-frame abnormal transcripts that possibly led to abolishment of important functional domains. To our knowledge, this is the first report of EVC mutations that cause EvC syndrome in Chinese population. Our data revealed that EVC splice site mutations altered splicing pattern and helped elucidate the pathogenesis of EvC syndrome.

Ellis–van Creveld Syndrome in Grey Alpine Cattle

Ellis–van Creveld (EvC) syndrome is a human autosomal recessive disorder caused by a mutation in either the EVC or EVC2 gene, and presents with short limbs, polydactyly, and ectodermal and heart defects. The aim of this study was to understand the pathologic basis by which deletions in the EVC2 gene lead to chondrodysplastic dwarfism and to describe the morphologic, immunohistochemical, and molecular hallmarks of EvC syndrome in cattle. Five Grey Alpine calves, with a known mutation in the EVC2 gene, were autopsied. Immunohistochemistry was performed on bone using antibodies to collagen II, collagen X, sonic hedgehog, fibroblast growth factor 2, and Ki67. Reverse transcription polymerase chain reaction was performed to analyze EVC1 and EVC2 gene expression. Autopsy revealed long bones that were severely reduced in length, as well as genital and heart defects. Collagen II was detected in control calves in the resting, proliferative, and hypertrophic zones and in the primary and secondary spongiosa, with a loss of labeling in the resting zone of 2 dwarfs. Collagen X was expressed in hypertrophic zone in the controls but was absent in the EvC cases. In affected calves and controls, sonic hedgehog labeled hypertrophic chondrocytes and primary and secondary spongiosa similarly. FGF2 was expressed in chondrocytes of all growth plate zones in the control calves but was lost in most EvC cases. The Ki67 index was lower in cases compared with controls. EVC and EVC2 transcripts were detected. Our data suggest that EvC syndrome of Grey Alpine cattle is a disorder of chondrocyte differentiation, with accelerated differentiation and premature hypertrophy of chondrocytes, and could be a spontaneous model for the equivalent human disease.

Ellis-Van Creveld syndrome: dental management considerations and description of a new oral finding

Ellis-Van Creveld is a rare syndrome with characteristic dental and orofacial findings. Dental management of patients with Ellis-Van Creveld syndrome can be complicated by the associated skeletal and cardiac abnormalities. Here, we present the dental and orofacial findings in a patient with Ellis-Van Creveld syndrome, describe a new oral finding, and discuss the dental management considerations.

Ellis-van Creveld Syndrome: Mutations Uncovered in Lebanese Families

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.

Major transitions in human evolution revisited: a tribute to ancient DNA

The origin and diversification of modern humans have been characterized by major evolutionary transitions and demographic changes. Patterns of genetic variation within modern populations can help with reconstructing this ∼200 thousand year-long population history. However, by combining this information with genomic data from ancient remains, one can now directly access our evolutionary past and reveal our population history in much greater detail. This review outlines the main recent achievements in ancient DNA research and illustrates how the field recently moved from the polymerase chain reaction (PCR) amplification of short mitochondrial fragments to whole-genome sequencing and thereby revisited our own history. Ancient DNA research has revealed the routes that our ancestors took when colonizing the planet, whom they admixed with, how they domesticated plant and animal species, how they genetically responded to changes in lifestyle, and also, which pathogens decimated their populations. These approaches promise to soon solve many pending controversies about our own origins that are indecipherable from modern patterns of genetic variation alone, and therefore provide an extremely powerful toolkit for a new generation of molecular anthropologists.