广西柳州地区4931例孕妇脊髓性肌萎缩症突变携带者的筛查及产前诊断

Screening for spinal muscular atrophy mutation carriers among 4931 pregnant women from Liuzhou region of Guangxi

目的对广西柳州地区4931例孕妇进行脊髓性肌萎缩症（spinal muscular atrophy，sMA）突变携带者筛查，了解本地区人群SMN1基因拷贝数异常的携带率。方法联合应用变性高效液相色谱（denaturing high—performance liquid chromatography，DHPLC）和多重PCR技术对孕妇进行SMN1基因的拷贝数检测，判断其是否为携带者，并计算携带者的频率。对携带者的配偶进行筛查，并为双方均为阳性者提供产前诊断。结果在4931例孕妇中，共检出SMN1拷贝数为1的携带者61例，检出率为1.2％。诊断SMNl纯合缺失胎儿1例。结论广西柳州地区SMA突变的携带率略低于中国南部其他地区。DHPLC可有效筛查SMA突变的携带者，为遗传咨询和产前诊断提供依据。

Objective To screen for carriers of SMN1 gene mutation, which underlies spinal muscular atrophy （SMA）, in 4931 pregnant women from Liuzhou region of Guangxi, and to determine the carrier rate. Methods Combined denaturing high-performance liquid chromatography （DHPLC） and multiple PCR techniques were used to detect the copy number of SMN1 gene. The carrier frequency was calculated. The spouse of the carrier was also screened, and prenatal diagnosis was provided to the couples who were both positive. Results Among the 4931 pregnant women, 61 were found to harbor only one copy of the SMN1 gene, which yielded a carrier rate of 1.2%. Subsequent testing has identified 1 fetus carrying homozygous deletions of the SMN1 gene. Conclusion The carrier rate of SMA mutation in Liuzhou region is slightly lower than that of other regions of southern China. DHPLC can effectively screen the carriers of SMA mutation and provide a basis for genetic counseling and prenatal diagnosis.