摘要目的：报告2例长岛型掌跖角化病，确定其致病基因突变。方法收集患者及其父母外周血和临床资料，提取基因组 DNA，PCR 扩增 SERPINB7基因8个外显子及其侧翼序列，对扩增产物进行 DNA 测序以查找基因突变位点，并以200例无关健康人 DNA 作为对照进行扩增测序。结果2例患者均存在 SERPINB7基因 c.796C > T 纯合突变，导致编码蛋白质第266位氨基酸出现终止改变（p.R266*），其父母均为 c.796C > T 杂合突变，而无关健康对照未发现上述突变。结论 SERPINB7基因的 c.796C > T 突变可能是引起2例患者长岛型掌跖角化病的原因。

abstractsObjective To report two cases of Nagashima-type palmoplantar keratoderma(NPPK), and to identify mutations in the SERPINB7 gene. Methods Clinical data were collected from two patients with NPPK and their parents, and peripheral blood samples were obtained from the two patients, their parents and 200 unrelated healthy controls. Genomic DNA was extracted from these blood samples. PCR was performed to amplify 8 exons and their flanking sequences of the SERPINB7 gene followed by DNA sequencing. Results A homozygous mutation (c.796C > T), which led to the formation of a premature termination codon at amino acid position 266 (p.R266*), was identified in both of the two patients. However, the patients′ healthy parents were heterozygous carriers of the mutation(c.796C > T). No mutation was found in the unrelated healthy controls. Conclusion The mutation c.796C > T in the SERPINB7 gene may be responsible for NPPK in the two patients.