胎儿脐带血产前诊断脊髓性肌萎缩症

目的:探讨脊髓性肌萎缩症(SMA)产前基因诊断的方法。方法:采集2例有SMA阳性家族史的胎儿脐带血,应用错配聚合酶链反应-限制性片段长度多态性分析(PCR鄄RFLP)技术对SMNt基因第7号外显子进行缺失检测。选择正常人及SMA患者作对照,另外检测了10例无遗传病家族史的胎儿脐带血。结果:2例胎儿,1例检测到SMNt基因纯合缺失,诊断阳性而终止妊娠,另1例未检测到SMNt基因纯合缺失视为正常儿予继续妊娠,结果顺利产出1名正常儿。10例胎儿均未检测到SMNt基因纯合缺失。结论:通过脐带血检测SMNt基因缺失可快速、可靠的对SMA进行产前诊断。

Prenatal diagnosis of spinal muscular atrophy based on umbilical cord blood

Objective:To investigate methods for prenatal diagnosis of spinal muscular atrophy. Methods:The umbilical cord blood of 2 fetuses with SMA positive family history was collected, then exon 7 of telomeric survial motor neuron(SMNt) gene was detected by using the technique of mismatching polymerase chain reaction-restriction fragment length polymorphism(PCR-RFLP). Normal member and SMA patient were selected as controls, at the same time the umbilical cord blood from 10 fetuses without heredofamilial history had also been detected. Results:In 2 fetuses, one was detected homozygous deletion of the SMNt exon 7, so was diagnosed as positive and the pregnancy was terminated, the other wasn't detected homozygous deletion of the SMNt exon 7. The pedigree diagnosed as negative continued to pregnancy, and gave birth to a normal baby. No homozygous deletion was found in 10 fetuses. Conclusion:Detecting the deletion of SMNt gene based on umbilical cord blood could be recommended as a rapid and reliable method for prenatal diadnosis of SMA.