Objective: 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.
Methods: 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.
Results: A mutation of AAT>AGT at codon 160 (N160S) was found in all patients but not in unaffected family members and 50 controls.
Conclusion: The mutation of AAT>AGT at codon 160 (N160S) is the disease-causing mutation in this Chinese pedigree with EPPK.