Abstract: Objective: To identify mutations of keratin 9 gene (KRT9) in a family with diffuse plamoplantar keratoderma (DPPK). Methods: DNA was extracted from the peripheral blood of the patients in a family (3 patients and 3?normal members) and 100 healthy controls. All the exons of KRT9 were amplified by PCR and direct DNA sequencing was performed by ABI PRISM-3700 sequenator. Results: A missense mutation (487C>T) in the KRT9 gene was identified in the three patients and none of mutation was found in 3 normal family members and healthy controls. Conclusion: The mutation of C487T in KRT9 gene is associated with the onset of diffuse?palmoplantar keratoderma in the?family.

Key words: diffuse plamoplantar keratoderma, vitiligo, hyperthyroidism, KRT9 gene