表皮松解性掌跖角化病一家系KRT9基因突变检测

目的：检测一表皮松解性掌跖角化病(epidermolytic palmoplantar keratoderma，EPPK)家系中患者及其家族成员的KRT9基因突变。方法：收集该EPPK家系先证者及其家族成员临床资料，提取他们及100例无亲缘关系的健康对照外周血DNA，PCR扩增KRT9基因编码区的全部外显子及其侧翼序列，对产物直接测序，同时进行突变点的功能预测。结果：该家系所有患者的KRT9基因1号外显子第482位碱基均发生错义突变c.482A>G(p.Asn161Ser)。家系中未患病者及100名正常对照中均未发现此突变。SIFT和Polyphen-2软件预测c.482A>G(p.Asn161Ser)突变为有害变异位点。结论：KRT9基因的突变c.482A>G(p.Asn161Ser)可能是导致该家系发生表皮松解性掌跖角化病的原因。

Mutation analysis of keratin 9 gene in a Chinese pedigree with epidermolytic palmoplantar keratoderma

Objective: To detect the mutations of the KRT9 gene in a Chinese family with epidermolytic palmoplantar keratoderma (EPPK). Methods: Clinical data and blood samples were collected from the proband of the pedigree with EPPK and their family members. PCR was performed to amplify all coding exons and their flanking sequences of KRT9 gene followed by direct DNA sequencing. 100 unrelated healthy persons served as the controls. The function of the protein encoded by the KRT9 gene was predicted. Results: A missense mutation of c.482A>G (p.Asn161Ser) was identified in all the five affected individuals in the pedigree, but not in unaffected individuals and 100 healthy controls. The mutation was pridicted to be detrimental variation by SIFT and Polyphen-2 software. Conclusion: The mutation of c.482A>G(p.Asn161Ser) in KRT9 gene may be responsible for the phenotype of EPPK in this pedigree.