Genotype­Phenotype Correlation in Chinese Patients with Dystrophic Epidermolysis Bullosa Pruriginosa

Abstract

Dystrophic epidermolysis bullosa pruriginosa (DEB-Pr) is a rare variant of dystrophic epidermolysis bullosa (DEB) due to dominant or recessive mutations in the COL7A1 gene. More than 40 mutations in COL7A1 have been described in DEB-Pr. The aim of this study was to understand the genotypephenotype correlation in Chinese patients with DEB-Pr. Three Chinese families with typical clinical features of DEB-Pr were studied. The results were analysed in association with the eight Chinese DEB-Pr patients reported in the literature. In the three Chinese families with DEB-Pr, we found two dominant cases with G1773R and c.6900+1G>C mutations, and one case with heterozygous G2701W mutation of uncertain inheritance mode. In the 10 Chinese patients with dominant type of DEB-Pr, 7 glycine substitutions and three splicing site mutations of exon 87 skipping were identified. Glycine substitution mutations in the triple helix region and exon 87 skipping, leading to the in-frame deletion of 23 amino acid residues in the triple-helix, are often seen in Chinese patients with dominant DEB-Pr, although the glycine substitutions are also frequently present in dominant DEB.