Monilethrix, a congenital disease of hair, is usually associated with mutations in keratin genes, like KRT81, KRT83 and KRT86. We conducted this study to investigate the mutation of type Ⅱ human basic hair keratin hHb/ KRT gene in a Han family with monilethrix and obtain information for potential pathogenic mechanism study of monilethrix. Peripheral blood samples were drawn for genomic DNA detection. Exon 1 and exon 7 of the KRT81, KRT83 and KRT86 genes were amplified by PCR. All PCR products were sequenced directly using an ABI 310 DNA sequencer. These sequences were aligned with the standard sequences in GenBank using the BLAST software. PCR products were digested with restriction endonuclease and restriction fragment length polymorphism (RFLP) analysis was performed. In this study, we identified one novel mutation, which is a heterozygous transitional mutation of G→A at position 1,289 in exon 7 of the KRT86 gene [R430Q (KRT86)]. RFLP assays for the novel mutation excluded the possibility of polymorphism. The R430Q mutation of the KRT86 gene may be pathogenic for monilethrix. Meanwhile, we did not find any novel mutation or recurrent mutation in exons 1 and 7 of KRT81 and KRT83 and exon 1 of KRT86. There is a potential pathogenic gene in the subjects and our results expand the spectrum of mutations in the hHb6 gene.
Jin Wu Yongli Lin Wenrong Xu Zhongming Li Weixin Fan
Hypertrichosis is one of the most common side effects of systemic cyclosporine A therapy.It has been previously shown that cyclosporine A induces anagen and inhibits catagen development in mice.In the present study,to explore the mechanisms of cyclosporine A,we investigated the effects of cyclosporine A on hair shaft elongation,hair follicle cell proliferation,apoptosis,and mRNA expression of selected growth factors using an organ culture model of mouse vibrissae.In this model,cyclosporine A stimulated hair growth of normal mouse vibrissae follicles by inhibiting catagen-like development and promoting matrix cell proliferation.In addition,cyclosporine A caused an increase in the expression of vascular endothelial growth factor(VEGF),hepatocyte growth factor(HGF),and nerve growth factor(NGF),and inhibited follistatin expression.Our findings provide an explanation for the clinically observed effects of cyclosporine A on hair growth.The mouse vibrissae organ culture offers an attractive model for identifying factors involved in the modulation of hair growth.