【摘要】 目的探讨羊水胎儿上皮细胞DNA-单核苷酸多态性(SNP)等位基因比率分析法快速诊断产前唐氏综合征的效果。方法选取产前诊断为21三体单胎妊娠的冻存羊水标本24例及产前诊断为二倍体单胎妊娠的标本76例。利用基质辅助激光吸收离子化时间飞行质谱技术(MALDI-TOF)对位于21号染色体上的一个SNP位点,rs7844进行了杂合度的检测,对杂合子样本进行等位基因比率分析。结果 100例羊水标本中,检出rs7844杂合子样本26例,其中21三体6例,二倍体20例。DNA-SNP等位基因比率分析诊断产前唐氏综合征只需1~2 d,但诊断敏感性可达100%。结论羊水细胞DNA-SNP等位基因比率分析可达到快速诊断产前唐氏综合征的目的。更多还原

【Abstract】 Objective To investigate the effect of amniocyte DNA-SNP allelic ratio on rapid diagnosis of prenatal Down syndrome. Methods A total of 100 frozen amniotic fluid samples of singleton pregnancy were selected,including 24 cases of trisomy 21 and 76 cases of euploid by prenatal diagnosis. The heterozygosity of rs7844,a single-nucleotide polymorphism(SNP) located in chromosome 21,was detected by using matrix-assisted laser desorption and ionization time-of-flight mass spectrometer analysis,and the DNA-SNP allelic ratios of those cases with heterozygous SNPs were determined. Results 26 cases with heterozygous SNP of rs7844 were found in 100 amniotic fluid samples,including 6 cases of trisomy 21 and 20 cases of euploid. The result of DNA-SNP allelic ratio for prenatal diagnosis of Down syndrome came out in 1 or 2 days,and its diagnostic sensitivity was 100%.Conclusion Amniocyte DNA-SNP allelic ratio analysis can be used for rapid prenatal diagnosis of Down syndrome.更多还原