Abstract: Objective: To identify the mutations of KRT6b and KRT17 genes in a pedigree with pachyonychia congenita. Methods: Genomic DNA was extracted from peripheral blood of propositus, the parents and 100 healthy controls. The mother was a patient and his father was normal. All the exons of KRT6b and KRT17 genes were amplified by PCR, and the products were purified and directly sequenced to detect mutations. Results: A missense mutation of KRT17 gene (c.275A>G) was identified in propositus and the mother, which was not found in the father and controls. No mutation of KRT6b was found in this family members and controls. Conclusion: A heterozygous missense mutation in KRT17 (c.275A>G, p.Asn92Ser) is the cause of the disease in the family.

Key words: pachyonychia congenita, gene mutation, KTR gene