A novel 7-bp deletion mutation in a Taiwanese family with X-linked hypohidrotic ectodermal dysplasia

Abstract

Hypohidrotic ectodermal dysplasia (HED) is found worldwide with an estimated incidence of 1 per 100,000 births. X-linked hypohidrotic ectodermal dysplasia (XLHED, OMIM 305100) is the most common form of the ectodermal dysplasias (ED), a rare group of hereditary diseases characterized by abnormal development of eccrine sweat glands, hair, and teeth. Heterozygous carriers of XLHED often manifest minor or moderate degrees of hypotrichosis, hypodontia, and hypohidrosis. ED1, the gene for XLHED encodes ectodysplasin A, which is a new member of the tumour necrosis factor family. The majority of mutations in XLHED are missense mutations, but one-fifth are insertion/deletions. Here we report a novel 7-bp deletion mutation (nt1242-1248) in exon 9 of the ED1 gene that results in a frameshift and premature stop codon (PTC + 38 amino acids). Mutation analysis in families with XLHED allows for genetic counselling, prenatal diagnosis and confirmation of carrier status.

Missense mutation of the EDA gene in a Jordanian family with X-linked hypohidrotic ectodermal dysplasia: phenotypic appearance and speech problems

“…In addition, XLHED may have emotional consequences for affected individuals at an early age (Yavuz et al, 2006). The clinical findings of the affected male in the family examined fall within the scope of previous reports showing defective development of hair, teeth, nails, and skin Chao et al, 2003;Lin et al, 2004;Na et al, 2004;Huang et al, 2006;Tao et al, 2006;Tariq et al, 2007;Fan et al, 2008). The defect in speech in the affected male could be due to the presence of the large diastema between the central incisors and the maladaptation in the production of the fricative sibilants (Sharma et al, 1978).…”

“…Mutations in any of these domains were reported to produce XLHED (Bayes et al, 1998;Ezer et al, 1999;Vincent et al, 2001;Chao et al, 2003). These mutations include small and large deletions (Vincent et al, 2001;Lin et al, 2004), frameshifts (Huang et al, 2006), insertions (Huang et al, 2006;Tariq et al, 2007) and substitution (Paakkonen et al, 2001;Na et al, 2004;Sekiguchi et al, 2005;Tao et al, 2006;Fan et al, 2008). The mutation described in this study is located in the amino terminal, extracellular domain, an essential hydrophilic domain required for proper function of ectodysplasin-A.…”

A novel frameshift mutation of theEDA1gene in a Chinese Han family with X-linked hypohidrotic ectodermal dysplasia

“…To date, 11 mutations in the EDA1 gene have been reported in Chinese families (Table 1). [4][5][6][10][11][12][13] It is interesting to note that there are six mutations located in exon 9, which suggests that mutations in exon 9 occur with a high frequency in…”

“…To date, > 100 mutations in the EDA1 gene have been described. [3][4][5][6] Most mutations in X-linked HED (XLHED) are missense mutations, but one-fifth are insertions ⁄ deletions.…”

Three novel mutations of the EDA gene in Chinese patients with X-linked hypohidrotic ectodermal dysplasia

“…Of these variants, the longest EDA‐A1 isoform encodes a protein of 391 amino acids. To date, more than 100 pathogenic mutations in the EDA gene have been described to be associated with XLHED 2–4,6–16 . About 80% of the EDA mutations are small intragenic changes, including point mutations, small deletions and insertions, more than half of which were found in exons 1, 3 and 5.…”