The Screening and Prenatal Diagnosis for SMN1 Gene in Pregnant Women

Abstract

Abstract: Objective：By conducting screening studies on the deletion mutations in exon 7 and exon 8 (E7, E8) of SMN1 gene in pregnant women, an accurate, rapid, simple, and high-throughput prenatal screening and diagnosis of this gene locus was established. SMA patients can be prevented. Methods：QF-PCR was used to screen the deletion of SMN1 gene E7 and E8 in 162 cases of women in mid-pregnancy. When the spouses were carriers of SMA pathogenic genes, fetal DNA was extracted to detect SMN1 gene deletion. The high-risk fetal MLPA genetic diagnosis was performed at the same time. Results：A total of 162 pregnant women were screened and the presence of SMN1 E7 heterozygous carriers were found in 6 cases. As for the QF -PCR test results of the carriers′ spouses，4 cases showed that E7 and E8 were all normal and 2 cases showed loss of heterogeneity. As to the two high-risk fetus whose both parents were SMA carriers，amniotic fluid DNA testing suggested that 1 fetus had E7 and E8 homozygous deletion, and the other one showed loss of heterogeneity. The results of MLPA were same with QF-PCR. Conclusions：QF-PCR can be used in the screening and diagnosis of SMA patients in large pregnant population. It has great clinical value to prevent the birth of SMA children.

Key words: Muscular atrophy, Polymerase chain reaction, SMN1 gene, Heterozygote detection, Chromosome aberrations, Prenatal diagnosis

REN Chen-chun, GUO Dong-hua, LIANG Yue-hong, WANG Wen-jing, TIAN Xiu-ying, CUI Hong-yan, CHEN Cheng-bin, WANG Ling-hong, YANG Wei-wei, ZHANG Hai-xia, LI Xiao-xu. The Screening and Prenatal Diagnosis for SMN1 Gene in Pregnant Women[J]. Journal of International Obstetrics and Gynecology, 2019, 46(2): 189-192.

References

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