Novel keratin 5 mutation in a family with epidermolysis bullosa simplex.

The aim of the present study was to identify the causative gene defects associated with epidermolysis bullosa simplex (EBS) in a pedigree. The diagnosis of EBS was confirmed in two patients from that pedigree based on the clinical manifestations, histopathological examination of the skin and family history. Blood samples were collected from 6 family members and 100 heathy controls, and genomic DNA and RNA were extracted. Mutation analysis of the keratin 5 gene (KRT5) was conducted using polymerase chain reaction (PCR) direct sequencing and PCR-restriction fragment length polymorphism. In the pedigree, the results of PCR direct sequencing revealed a heterozygous missense mutation in codon 202 of exon 2 of KRT5 (c.605T>A), which led to an amino acid change (p.L202Q) in the patients with EBS but was absent from the unaffected family members and 100 population controls. In conclusion, a novel missense mutation in the KRT5 gene was identified that had a pathogenic role in EBS in the population studied, which enriches the germline mutation spectrum of the KRT5 gene.