A frameshift mutation of the ED1 gene in sibling cases with X-linked hypohidrotic ectodermal dysplasia

Abstract

X-linked hypohidrotic ectodermal dysplasia (XLHED; MIM 305100) is characterized by the absence or hypoplasia of hair, teeth, and sweat glands. The ED1 gene was identified as a responsive gene for XLHED. The patients were 2 Japanese brothers. Both had the same mutation in exon 1 of the ED1 gene, i.e. C deletion at nucleotide 49, which induced a frameshift starting from amino acid 17 and made a stop codon at amino acid 56, encoding the transmembrane site. The mutation caused the extracellular domain of ectodysplasin A to be completely absent. Their mother had a heterozygous allele; she congenitally lacked 1 tooth, and incisors appeared conical in form.