Keratin 1 and keratin 10 mutations causing epidermolytic hyperkeratosis in Chinese patients.

Epidermolytic hyperkeratosis (EHK) is a rare dominantly inherited skin disorder with erythroderma and hyperkeratosis. Mutations have been found in keratin 1 (K1) or keratin 10 (K10) gene. In the present study, we reported three sporadic and one familial Chinese EHK patients with their mutation findings. All the mutations turned out to be single heterozygous point substitutions. A novel mutation designated as E477K of K1 was identified in one patient, and previous reported mutations in codon 156 of K10, i.e. R156S, R156P, R156H were found in other patients. This is the first report of the keratin mutations in Chinese kindreds. The results showed that the possible correlation between the genotype and phenotype in these patients was complex, not only depended on the position of the mutation but also on the actual amino acid substitution. And palmoplantar keratoderma (PPKD) can be an accompanied symptom caused by either K1 or K10 mutation.