摘要
目的探讨无创产前检测(NIPT)在胎儿染色体微缺失/微重复检测中的应用价值。方法对26例NIPT提示存在染色体缺失和/或重复的孕妇行羊膜腔穿刺术,进行染色体核型分析及低覆盖度全基因组测序技术检测拷贝数变异。结果NIPT提示存在染色体信号异常的26例孕妇中,经染色体核型分析及拷贝数变异检测确诊11例,符合率42.31%(11/26)。其中18例NIPT明确提示存在染色体的缺失或重复,经验证后确诊9例,符合率50.00%(9/18),且缺失和/或重复的位置及片段大小与NIPT结果基本一致。结论将NIPT的筛查范围扩大到胎儿全基因组拷贝数变异的检测,从技术上来说是可行的。
Objective:To investigate the clinical application value of noninvasive prenatal testing for detection of fetal subchromosome abnormalities. Methods:Amniotic fluid amniocentesis and karyotype analysis and CNV sequencing were sampled from 26 pregnant women whose NIPT results were abnormal. Results:The sensitivity was determined to be 42.31% in testing26 samples.9 cases that detected genomewide gains and losses of chromosomal material were confirmed by CNV sequencing.Conclusion:Noninvasive prenatal testing can be expanded into the detection of subchromosomal copy number variations. The limit of detection for CNV is constrained by fetal fraction,microdeletion/microduplication size and coverage.
引文
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