[Mutation analysis of keratin 9 gene in a pedigree with epidermolytic palmoplantar keratoderma].

To identify mutations of keratin 9 (KRT9) gene in a big Chinese family with epidermolytic palmoplantar keratoderma(EPPK) combined with knuckle-pad-like lesions and nail lesions.Genomic DNA from peripheral blood of all available members in this family and 50 unrelated healthy individuals was used for amplification of the whole coding sequence and the intron-exon boundaries of KRT9 gene by PCR; The mutation was detected by direct sequence analysis and identified by restriction endonuclease Dde I.A mutation of AAT>AGT at codon 160 (N160S) was found in all patients but not in unaffected family members and 50 controls.The mutation of AAT>AGT at codon 160 (N160S) is the disease-causing mutation in this Chinese pedigree with EPPK.