萍乡地区1241例孕妇脊髓性肌萎缩症携带者筛查及产前诊断分析

Analysis of spinal muscular atrophy carrier screening and prenatal diagnosis of 1241 preg-nant women in Pingxiang area

目的对萍乡地区1241例孕妇进行脊髓性肌萎缩症(SMA)突变的携带者筛查,探究人运动神经元存活基因1(SMN1)变异携带率并分析SMA产前诊断的临床意义。方法采用PCR-熔解曲线法技术对1241例孕妇全血样本进行SMN1基因第7和第8外显子(E7、E8)缺失情况检测,对结果确定为杂合缺失的孕妇配偶进行SMN1基因检测,为双方都是携带者的夫妻进行产前诊断,采用多重连接探针扩增技术(MLPA)对夫妻双方用MLPA方法进行复检,同时确认胎儿SMN1基因型。结果在1241例孕妇中,共检出SMA携带者16例,其中E7、E8同时杂合缺失15例,单纯E7杂合缺失1例,携带率为16/1241(1.29%)。检出夫妻双方同为SMA携带者1对,经MLPA方法检测,最终确认胎儿为SMN1基因E7、E8纯合缺失。结论SMA携带者筛查可对高风险胎儿进行筛选,有效预防SMA患儿的出生,对出生缺陷防控及减轻家庭经济及精神负担具有重要意义。

Objective To investigate the mutation carrier rate of human motor neuron survival gene 1(SMN1)and analyze the clinical significance of prenatal diagnosis of SMA in 1241 pregnant women in Pingxiang area.Methods PCR technique was used to detect the deletion of exon 7 and exon 8(E7,E8)of SMN1 gene in 1241 pregnant women.The husbands of pregnant women carrier were also screened,and prenatal genetic analysis was provided for the couples with both positive results.The results were further confirmed by multiplex ligation-dependent probe amplification(MLPA).Results Among 1241 pregnant women,a total of 16 SMA carriers were detected,including 15 cases of simultaneous heterozygosity deletion of E7 and E8,and 1 case of single heterozygosity deletion of E7,with a carrying rate of 16/1241(1.29%).One pair of both spouses were found to be SMA carriers.It was finally confirmed that the fetus had homozygous deletion of SMN1 gene E7 and E8 by MLPA technique.Conclusion SMA carrier screening can screen high-risk fetuses and effectively prevent the birth of SMA children with SMA.It is of great significance to the prevention and control of birth defects and reducing family economic and mental burdens.