无创产前检测技术在双胎染色体非整倍体疾病筛查中应用研究

Noninvasive prenatal testing of fetal chromosomal aneuploidy diseases in twin pregnancies

目的探讨无创产前检测技术在双胎染色体非整倍体疾病筛查中的临床应用价值。方法对2015年10月1日至2016年8月1日在中国医科大学附属盛京医院就诊,自愿接受无创产前检测的423例妊娠12~31周双胎孕妇,抽取外周血获取胎儿游离DNA,应用高通量测序技术检测胎儿非整倍体的情况。无创检测的结果由羊水细胞及分娩时脐血核型分析进行验证。结果无创产前检测异常者8例,4例提示21-三体高风险,2例提示18-三体高风险,2例提示X染色体单体（45,X）。6例三体高风险胎儿经羊水或脐血穿刺检查结果确认无误。1例X染色体单体的羊水结果与检测结果一致,另1例羊水检测结果正常,但随后确认该孕妇核型为46,XX[36]/45,X[64]。经验证的低风险者176例,均与其一致。结论无创产前检测作为一种快速、安全的产前筛查手段,在双胎的非整倍体疾病筛查中有较高的灵敏度和特异度,具有临床应用价值。

Objective To explore the value of noninvasive prenatal testing in fetal chromosomal aneuploidy diseases in twin pregnancies. Methods A total of 423 twin pregnant women were recruited from Shengjing Hospital of China Medical University during October 1st,2015 to August 1st,2016. They agreed to accept noninvasive prenatal testing and would delivery in our hospital. Maternal peripheral blood was collected and free fetal DNA was extracted, and highthroughput sequencing technology was performed to detect the fetal aneuploidies. The fetal karyotypes of amniotic fluid cells or umbilical cord white blood cells were used as gold standard to estimate the sensitivity and specificity of noninvasive prenatal testing.Results In 8 out of 423 twin pregnant women, noninvasive prenatal testing revealed chromosome abnormalities, including 4 cases of high risk for 21-trisomy, 2 cases of high risk for 18-trisomy and 2 cases of X-monosomy. Six cases of T21 and T18 were all confirmed by karyotyping. One case of X-monosomy was consistent with karyotyping. Another case of X-monosomy was confirmed normal through karyotyping, but then we found the mother＇s karyotype was mosaic 46, XX[36]/45, X[64].176 cases of low risk through NIPT accorded with karyotyping.Conclusion Noninvasive prenatal testing can detect fetal chromosomal aneuploidy rapidly and accurately in twin pregnancies,and it is highly sensitive and specific, which is of great value in clinical application.