The Second Deletion Mutation in Exon 8 of <b><i>EDA</i></b> Gene in an XLHED Pedigree

Abstract

Background: X-linked hypohidrotic ectodermal dysplasia (XLHED) is characterized by hypodontia, hypohidrosis, sparse hair and characteristic facial features and is caused by mutation in the ectodysplasin A (EDA) gene. Objective: In this study we report on a large Chinese XLHED family and investigate the molecular genetics of the defect. Methods: All individuals of the family were examined by clinical and radiographic examinations. The EDA gene was sequenced in the whole family and in 150 controls. Results: Three male patients had classic XLHED phenotype. A novel one-nucleotide deletion mutation (c.855delG) in exon 8 which caused premature termination of the polypeptide at amino acid 307 was confirmed. The mutant lost parts of the TNF domain may prevent transmission of the intracellular downstream signal. This was the second deletion mutation in exon 8 that was reported in a Chinese individual. Conclusions: Our findings suggested deletion mutations in exon 8 might be specific to the Chinese population.

The phenotypic characteristics of patients with athelia and tooth agenesis

“…which is characterized by the dysplasia of ectodermal structures (5)(6)(7). Patients present with defects relating to hair, nails, teeth, and sweat glands.…”

Hypodontia, a prospective predictive marker for tumor?

“…TP63 is a master regulator of epidermal development and operates as a transcriptional activator and repressor regulating the expression of several groups of genes. Mutations of TP63 are responsible for at least five different syndromes [EEC, ankyloblepharon–ectodermal dysplasia–clefting (AEC), acro‐dermato‐ungual‐lacrimal‐tooth (ADULT), limb–mammary syndrome (LMS), and Rapp–Hodgkin ectodermal dysplasia (RHS)] that exhibit developmental defects including hypodontia (Yin et al , ).…”

Ectodermal Dysplasia: Thoughts and Practical Concepts Concerning Disease Classification - The Role of Functional Pathways in the Molecular Genetic Diagnosis

“…Most syndromic forms of ectodermal dysplasias are recognized by particular clinical features [1]. In this issue, Yin et al [2 ]described a deletion mutation in exon 8 of the EDA (ectodysplasin-A) gene as a cause for X-linked hyphidrotic ectodermal dysplasia. Hypohidrotic ectodermal dysplasia can develop from different mutations belonging to the TNF-α-like signaling pathway.…”