摘要目的 研究1个先天性厚甲症Ⅱ型家系的基因突变情况.方法 收集该家系的详细临床资料,外周血提取基因组DNA,PCR扩增KRT17热点突变区,通过PCR扩增产物直接测序方法对该家系患者、正常成员和100名无亲缘关系的正常人进行KRT17基因突变检测.结果 在该家系患者KRT17基因的第1外显子上发现了1个错义突变(296 T→C),导致KRT17的1A区亮氨酸由脯氨酸替代(L99P),而家系中正常成员和家系外100名正常对照中均未能发现该突变.结论 该家系患者的临床表现为KRT17发生突变(L99P)所致,结合文献复习证实部分PC-Ⅱ家系基因型与表现型之间存在一定相关性.

abstractsObjective To investigate the keratin 17 gene (KRT17)mutation in a pedigree with pachyonychia congenita type 2 (PC-Ⅱ ). Methods DNA was extracted from the blood samples of the patients, unaffected members of the pedigree, and 100 unrelated healthy controls. PCR was performed to amplify the hot spots in KRT17 gene. PCR products were directly sequenced to detect mutation. Results A heterozygous 296T--C mutation was found in all the affected members of this family, which resulted in the substitution of leucine by proline in codon 99 (L99P) in the 1A domain of the KRT17, but not in the healthy individuals from the family and the 100 unrelated controls. Conclusion The mutation of KRT17 may play a major role in the pathogenesis of this pedigree with pachyonychia congenita type 2.