Ellis-van Creveld syndrome
Ellis-van Creveld syndrome is an autosomal recessive skeletal dysplasia, which is characterized by short stature, retarded growth, polydactyly, and ectodermal and heart defects. The first case of EVC syndrome was reported by Mclntosh in 1933, but Richard W, B, Ellis of Edinburgh, and Simon van Creveld of Amsterdam in 1940, first described this condition and defined it as EVC syndrome. It is also known as chondroectodermal dysplasia and meso-ectodermal dysplasia.
The features of Ellis-van Creveld syndrome overlap with those of another, a milder condition called Weyers acrofacial dysostosis. Like Ellis- van Crevelf syndrome, Weyers acrofacial dysostosis involves tooth and nail abnormalities, although affected individuals have less pronounced short stature and typically do not have heart defects. The two conditions are caused by mutations in the same genes.
Inheritance:
This condition is inherited in autosomal recessive patterns which means both copies of the gene in each cell have mutations. The parents of an individual with an autosomal recessive condition each carry one copy o the mutated gene, but they typically do not show signs and symptoms of the disease.
Causes:
Ellis- van Creveld is passed down through families. it is caused by defects in 1 of 2 Ellis-van Crevel syndrome genes (EVC and EVC2). These genes are positioned next to each other on the same chromosome. The severity of the disease varies from person to person. The rights rate of the condition is seen among the Old Order Amish population of Lancaster County, Pennsylvania. It is fairly rare in the general population.
Symptoms: Include
- Cleft lip or palate
- Epispdis or undescended testicle (cryptorchidism)
- Extra fingers (polydactyly)
- Limited range of motion
- Nail problems, including missing or deformed nails
- Short arms and legs, especially forearm and lower leg
- Short height, between 3.5 to 5 feet
- Spares, absent, or fine-textured hair
- Tooth abnormalities, such as peg teeth, widely-spaced teeth
- Teeth present at birth (natal teeth)
- Delayed or missing teeth
Disorders with similar symptoms:
Ellis- van Creveld syndrome is in the category of rare skeletal disorders called short rib- polydactyly syndromes, belonging to the ciliopathies group.
These disorders are characterized by growth deficiency resulting in short stature, abnormally short ribs, extra fingers and toes, and variable visceral manifestations. These additional findings may include polycystic kidneys, underdevelopment of the lungs, vertebral and genitourinary abnormalities, central nervous system abnormalities, and cleft lip and cleft palate. They are inherited as autosomal recessive genetic conditions.
The short rib- polydactyly group includes 4 antenatal lethal types, saldino-Noonan, Majewski, Verma- Naumoff, and Beemer- Langer syndromes, and 2 types compatible with life, EVC, and Asphyxiating Thoracic Dystrophy or Jeune syndrome.
ATD is characterized by variable respiratory insufficiency due to thorax narrowness, kidney, liver, and retinal abnormalities, and inconstant short stature. At least two genes are associated with this condition. The neonatal clinical presentation overlap with EVC features, especially in the absence of heart abnormalities.
Weyers acrofacial dysostosis is another genetic disorder associated with polydactyly, dental and nail abnormalities, short stature, and abnormal facial features. This condition has been found to be associated with a single mutation in either the EVC or EVC2 gene and follows autosomal dominant inheritance.
Diagnosis:
Ellis- Van Creveld syndrome is diagnosed by the observation of short stature, slow growth, and skeletal abnormalities determined by imaging techniques and sometimes teeth present at birth (natal teeth). Molecular genetic testing for the EVC and EVC2 genes is available on a research basis only. Prenatal diagnosis is possible by ultrasound.
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