染色体微阵列分析在无创产前筛查非整倍体高风险中的应用价值

目的:探讨染色体微阵列分析(CMA)技术在无创产前筛查(NIPT)提示非整倍体高风险胎儿的产前诊断中的应用价值。方法:241例NIPT提示胎儿染色体非整倍体高风险的孕妇,经羊膜腔或绒毛穿刺获取胎儿细胞,进行CMA分析。对于NIPT提示21-三体和性染色体非整倍体高风险的孕妇根据筛查原因(高龄筛查组、唐筛异常或超声软指标异常组、非高龄筛查组)进行组间NIPT阳性预测值的比较,并对CMA检测提示有染色体拷贝数变异(CNV)的病例进行致病性分析。结果:NIPT对于染色体非整倍体总的阳性预测值为76.3%。NIPT对于21-三体、18-三体、13-三体和性染色体非整倍体的阳性预测值分别为95.0%、88.8%、75.0%和53.3%。经CMA分析确认,在101例NIPT提示21-三体高风险病例中,以高龄筛查组阳性预测值最高(100.0%),3组间比较,差异有统计学意义(P=0.001)。在90例NIPT提示性染色体非整倍体高风险病例中,仍以高龄筛查组阳性预测值最高(61.9%),3组间比较,差异有统计学意义(P=0.002)。12例NIPT提示染色体非整倍体高风险经CMA检测存在CNV。结论:...

Application of Chromosomal Microarray Analysis in the Prenatal Diagnosis of High-Risk of Aneuploidy by Noninvasive Prenatal Test

Objective:To assess the value of chromosomal microarray analysis(CMA)in the prenatal diagnosis of high-risk of aneuploidy suggested by noninvasive prenatal test(NIPT).Methods:241 pregnant women with high risks of aneuploidysuggested by NIPT were subjected to CMA analysis.The cells for CMA analysis were obtained by amniocentesis and chorionic villus sampling.According to the reasons of screening,the patients were divided into three groups:advanced age screening group,abnormal Down syndrome screening or abnormal ultrasound soft marker group,and non-advanced age screening group.For pregnant women with high risk of 21 trisomy and sex chromosome aneuploidy suggested by NIPT,NIPT positive predictive values were compared among groups according to the screening reasons,and the pathogenicity of copy number variations(CNV)cases suggested by CMA was analyzed.Results:The total positive predictivevalue of NIPT for chromosome aneuploidy was 76.3%.The positive predictive value of NIPT for 21,18,13-trisomyand sex chromosome aneuploidy were 95.0%、88.8%、75.0% and 53.3% respectively.CMA analysis confirmed that among 101 NIPT high-risk cases with 21-trisomy,the advanced age screening group had the highest positive predictive value(100.0%).There were statistically significant difference among three groups(P=0.001).Among 90 cases with high risk of sexual chromosome aneuploidy suggested by NIPT,the positive predictive value was the highest in the advanced age screening group(61.9%),also with statistically significant differences among three groups(P=0.002).There were chromosomal CNV detected by CMA in 12 cases with high risk of chromosomal aneuploidy suggested by NIPT.Conclusions:For 21-trisomy and sex chromosome aneuploidy,the most significant NIPT positive predictive value is found in the advanced age groups.In clinic,we should pay more attention to this kind of people and do a good follow up.Compared with the traditional chromosome karyotype analysis,CMA can detect CNV and improve the detection rate of chromosomal structural abnormalities.