[Analysis of human hair basic keratin 6 gene mutation in a Chinese Han family with monilethrix].

OBJECTIVE: To identify the human hair basic kerat in 6 gene (hHB6) gene mutation in a mother and her daughter with monilethrix.

METHODS: Clinical data were obtained by investigating the pedigree and examining the patients' hair and skin. Total genomic DNA of the family participants was isolated. All exons and exon-intron boundaries of hHB6 were amplified by PCR. Mutation screening was carried out using direct DNA sequencing. Restriction fragment length polymorphism (RFLP) analysis was used to confirm the mutation, and to investigate if the mutation co-segregated with the disease in the family and existed in normal controls.

RESULTS: A heterozygous transition of c.1204G to A (p.E402K) of hHB6 was identified. RFLP analysis demonstrated that affected members carried the p.E402K mutation, but the unaffected members of the family and 150 unrelated normal Chinese Han nationality controls did not carry the mutation.

CONCLUSION: This study identified the hHB6 gene mutation c.1204G to A (p.E402K) in a Chinese monilethrix family. The mutation was inherited from the mother to her daughter. The results emphasized the key role of hair keratin hHB6 in the pathogenesis of monilethrix and indicated that the common mutation of hHB6 was also a cause of monilethrix in Chinese.