同时检测两种运动神经元存活基因第7外显子缺失的简便方法及其临床应用

目的：建立同时检测运动神经元存活基因SMNT和SMNC第7外显子缺失的简便方法，用于儿童期起病的脊髓性肌萎缩症（SMA）的临床诊断。方法：应用聚合酶链反应（PCR）－限制性酶切技术，用一对引物同时扩增55例正常成年人和5例SMA患儿及其父母的SMN基因2个成员的第7外显子中的高度保守区，扩增产物经限制性内切酶酶切及非变性聚丙烯酰胺凝胶电泳。结果：此法可检测2个SMN基因第7外显子的缺失情况，经检测，55例正常成人均无SMNT基因第7外显子缺失，SMNC基因第7外显子缺失仅3例，5例SMA患儿的SMNT基因第7外显子均有缺失，患儿父母无SMNT基因和SMNC基因第7外显子缺失，结论：此法对检测2个SMN基因第7外显子的缺失提供了简便，特异，且适合临床特别是基层医院应用，优于PCRSSCP分析的方法。

Clinical utility of a simple method for detecting deletion of exon 7 of two suvival motor neuron and SMNC gene

Objective To establish a simple method for detecting deletion of exon 7 of the SMN gene included two members(SMNT and SMNC) at the same time , and diagnosing childhood onset spinal muscular atrophy(SMA) and analyzing deletion frequency of exon 7 of the SMNT/SMNC gene in normal chinese human.Methods One pair primer was used to amplify the high conservative region in exon 7 of two members of SMN gene in firty five normal adults,five SMA patients and their parents by PCR. A PCR restriction enzyme digestion PAGE technique was applied.Results Deletion of exon 7 in the SMNT gene was found in all five SMA patients, whereas deletion of exon 7 in the SMNC gene was found in 3 of 55 normal adults who haven't found the deletion of exon 7 in the SMNT gene.Conclusion The method is simple and special. It is better than the traditional way based on PCR SSCP and is useful for the genetic diagnosis of SMA in the hospital at the basic level.