A novel heterozygous missense mutation of DSP in a Chinese Han pedigree with palmoplantar keratoderma.

Abstract

Mutations in the desmoplakin (DSP) gene have been demonstrated to be associated with lethal acantholytic epidermolysis bullosa, cardiomyopathy, and palmoplantar keratoderma (PPK). To better understand the relationship between PPK and the gene mutations in DSP. A pedigree of PPK was subjected to heterozygous missense mutation analysis in the DSP gene. Dermoscopy, reflectance confocal microscopy, and histopathological examination were performed from each epidermis layer in this study. Samples were derived from the blood of patients and normal healthy controls. DSP gene sequence analysis and Q-PCR analysis was performed for evaluating DSP gene mutation and expression. A novel heterozygous missense mutation c.3550 C>T in the coding region of the DSP gene, predicting substitution of arginine (Arg,R) by tryptophan (Trp,W) in the desmoplakin polypeptide, was discovered in a Chinese pedigree of PPK. In the meanwhile, this mutation was not found in 100 healthy individuals. The novel missense mutation c.3550 C>T(p.Arg1184Trp) of DSP gene expanded the mutation spectrum in palmoplantar keratoderma.