Identification of a Novel Missense Mutation in EDAR Causing Autosomal Recessive Hypohidrotic Ectodermal Dysplasia with Bilateral Amastia and Palmoplantar Hyperkeratosis

Ectodermal dysplasias (EDs) are a large group of heritable complex conditions with more than 200 members and common clinical characteristics of anomalies of the hair, teeth, nails, and sweat glands with or without involvement of other organs (1) . Anhidrotic or hypohidrotic ectodermal dysplasia (EDA/ HED) is the most common form of EDs which is characterized by the clinical triad of hypotrichosis (sparse hair), abnormal or missing teeth (anodontia or hypodontia), and deficient sweating (hypohidrosis or anhidrosis) (2) . Different modes of inheritance have been described for HED. X-linked HED (OMIM: 305100) is caused by mutations in ectodysplasin A gene (EDA1), whereas mutations in the EDA receptor (EDAR) and EDAR-associated death domain (EDARADD) genes result in autosomal dominant (OMIM:129490) and autosomal recessive (OMIM: 224900) forms (3)