【摘要】 目的 本文对脊肌萎缩症基因诊断的敏感性与特异性进行了研究。方法 通过PCR、错配PCR、酶切的方法，对21例患儿(17例临床诊断，4例临床可疑)、患儿的父母34例、患儿的兄弟1例、健康对照5例进行了SMN基因突变分析。结果 在17例临床诊断为SMA的患儿中16例(94.1%)证实存在SMNt第7和第8外显子的纯合缺失。4例临床可疑病例、所有患儿父母及兄弟、健康对照均未发现此纯合突变。结论 应用PCR结合酶切对脊肌萎缩症的基因诊断方法简单、准确而且特异，具有很高的临床应用价值，并使脊肌萎缩症的症状前与产前诊断成为可能。

    Song Fuying，Bao Xinhua，Pan Hong，et al.

    Pediatric Department，Peking University First Hospital，Beijing100034.

    【Abstract】 Objective To study the sensitivity and specificity of gene mutational analysis.Methods In this study，SMNt gene mutational analysis was performed on21patients(17clinical diagnosed cases and4suspicious cases)，34parents，1brother and5controls by PCR，mis-match PCR and restriction endonuclease digestion.Results 16/17of clinical diagnosed cases have homozygouse deletion of exon7and exon8of SMNt，there are no homozygous mutation in4suspicious cases，34parents，1brother and5controls.Conclusion This SMNt gene mutaitonal analysis is a simple，rapid and effecient method for DNA-based SMA diagnosis，it should be used in the clinical test.

    Key words spinal muscular atrophy mutational analysis sensitiivity specificity ......