A novel missense mutation in the EDA gene associated with X-linked recessive isolated hypodontia

作者：Rasool Mahmood; Schuster Jens; Aslam Muhammad; Tariq Muhammad; Ahmad Ilyas; Ali Amjad; Entesarian Miriam; Dahl Niklas^*; Baig Shahid Mahmood

来源：Journal of Human Genetics, 2008, 53(10): 894-898.

DOI：10.1007/s10038-008-0323-x

• X-linked recessive hypodontia
• EDA gene
• missense mutation
• EDA model

Isolated hypodontia, or congenital absence of one to six permanent teeth (OMIM 300606), is a common condition that affects about 20% of individuals worldwide. We identified two extended Pakistani pedigrees segregating X-linked hypodontia with variable expressivity. Affected males show no other associated anomalies, and obligate carrier females have normal dentition. We analyzed the families with polymorphic markers in the ectodysplasin A (EDA) gene region and obtained significant linkage to the phenotype in each pedigree (Z(max) 3.29 and 2.65, respectively, at theta = 0.00). Sequence analysis of the coding regions of EDA revealed a novel missense mutation c.1091T > C resulting in a methionine to threonine substitution (p.M364T) in the tumor necrosis factor (TNF) homology domain. Met364 is a highly conserved residue located on the outer surface of the EDA protein. From our findings, we suggest that the mutation disturbs but does not destroy the EDA structure, resulting in the partial and unusually mild ED phenotype restricted to hypodontia.

• 出版日期2008-10