METHODS: We retrospectively analyzed NIPT data from 9,176 women with singleton pregnancies referred to the CHA Biotech genome diagnostics center. Cell-free fetal DNA (cffDNA) was extracted from maternal peripheral blood, and high-throughput massively parallel sequencing was conducted. Subsequently, the positive NIPT results for SCA were validated via karyotype and chromosomal microarray analyses.
RESULTS: Overall, 46 cases were SCA positive after NIPT, including 20, 12, 8, and 6 for Turner, triple X, Klinefelter, and Jacob syndromes, respectively. Among 37 women with invasive prenatal diagnosis, 19 had true positive NIPT results. The overall positive predictive value (PPV) of NIPT for detecting SCAs was 51.35%. The PPV was 18.75% for Turner, 88.89% for triple X, 71.43% for Klinefelter, and 60.00% for Jacob\'s syndromes. NIPT accuracy for detecting sex chromosome trisomies was higher than that for sex chromosome monosomy (P = 0.002). No significant correlation was observed between fetal SCA incidence and maternal age (P = 0.914), except for the borderline significance of Jacob\'s syndrome (P = 0.048). No significant differences were observed when comparing NIPT and karyotyping validation for fetal SCA according to pregnancy characteristics.
CONCLUSIONS: Our data suggest that NIPT can reliably screen for SCAs, and it performed better in predicting sex chromosome trisomies compared with monosomy X. No correlation was observed between maternal age and fetal SCA incidence, and no association was observed between different pregnancy characteristics. The accuracy of these findings requires improvements; however, our study provides an important reference for clinical genetic counseling and further management. Larger scale studies, considering confounding factors, are required for accurate evaluation.
方法:我们回顾性分析了来自CHABiotech基因组诊断中心的9176例单胎妊娠妇女的NIPT数据。从母体外周血中提取无细胞胎儿DNA(cffDNA),并进行了高通量大规模平行测序。随后,通过核型和染色体微阵列分析验证了SCA的NIPT阳性结果.
结果:总体而言,46例NIPT后SCA阳性,包括特纳的20、12、8和6,三重X,Klinefelter,和雅各布综合症,分别。在有侵入性产前诊断的37名妇女中,19具有真正阳性的NIPT结果。NIPT检测SCAs的总阳性预测值(PPV)为51.35%。特纳的PPV为18.75%,三X为88.89%,Klinefelter的71.43%,雅各布综合征为60.00%。NIPT检测性染色体三体的准确性高于性染色体单体(P=0.002)。胎儿SCA发生率与产妇年龄之间无显著相关性(P=0.914)。除Jacob综合征的临界意义外(P=0.048)。当根据妊娠特征比较胎儿SCA的NIPT和核型分析验证时,没有观察到显著差异。
结论:我们的数据表明,NIPT可以可靠地筛选SCA,它在预测性染色体三体中的表现优于单体X。没有观察到母亲年龄和胎儿SCA发病率之间的相关性,不同妊娠特征之间未观察到相关性。这些发现的准确性需要改进;然而,本研究为临床遗传咨询和进一步管理提供了重要参考。更大规模的研究,考虑到混杂因素,需要准确的评估。