A KRT16 mutation in the first Chinese pedigree with Pachyonychia congenita and review of the literatures.

BACKGROUND

Pachyonychia congenita (PC), a rare autosomal dominant disorder, is featured by significant hypertrophic nail, palmoplantar keratoderma, and plantar pain. It is caused by the mutation of KRT6A, KRT6B, KRT6C, KRT16, or KRT17.

AIMS: To identify the gene mutation caused the PC in a Chinese family.

PATIENTS/

METHODS

Genomic DNA was extracted from peripheral blood samples of five patients and six healthy individuals. Genomic DNA of three patients was sequenced by whole-exome sequencing (WES). Then, exons 6 of KRT16 of all samples were amplified by polymerase chain reaction (PCR), and PCR products were sequenced to identify potential mutations.

RESULTS

We identified the proline substitution mutation p.Leu421Pro (c.1262T>C) in the 2B domain of K16 that is associated with PC in a Chinese family. The same mutation was not found in the six healthy individuals of the family.

CONCLUSIONS

The mutation found in this study is the first report in China. So far, 25 mutations in KRT16 have been reportedly associated with PC. Twenty-one mutations are located on exon 1, and four mutations on exon 6.