染色体微阵列分析方法诊断侧脑室增宽胎儿的临床价值

Clinical value of genome-wide chromosome microarray technique in diagnosis of fetal cerebral ventriculomegaly

目的探讨染色体微阵列分析(CMA)在侧脑室增宽胎儿中遗传病因诊断的临床应用价值。方法回顾性分析2014年1月~2016年12月因超声提示"胎儿侧脑室增宽"于南方医科大学南方医院产前诊断中心同时行常规核型分析和CMA芯片检测109例单胎妊娠孕妇。比较侧脑室增宽胎儿核型分析和CMA芯片的染色体异常检出率。结果(1)核型分析的异常检出率为12.84%;CMA芯片的异常检出率为26.60%;两种检测的异常检出率比较,差异有统计学意义(P=0.011),核型分析结合CMA芯片的异常检出率为28.44%,核型分析结合CMA芯片能有效提高异常检出率。(2)17例侧脑室增宽胎儿中,核型分析显示正常而CMA芯片显示异常,额外异常检出率为15.60%。其中微缺失6例、微重复9例、微缺失合并微重复1例,单亲二倍体杂合缺失1例。结论 CMA技术可敏感检出侧脑室增宽胎儿的染色体拷贝数异常,提高异常检出率,有利于侧脑室增宽胎儿的产前咨询和预后评估。

Objective To investigate the clinical value of gnome-wide chromosome microarray（CMA） technique in genetic etiological diagnosis of fetal cerebral ventriculomegaly. Methods A retrospective analysis was conducted in 109 women with singleton pregnancy, who were admitted in Nanfang Hospital with the diagnosis of cerebral ventriculomegaly in the fetuses by ultrasound between January, 2014 and December, 2016. Routine karyotype analysis and chromosome microarray analysis were performed to identify the chromosomal abnormalities in the fetuses. Results Karyotype analysis detected chromosomal abnormalities at a rate of 12.84% in these fetuses, significantly lower than the rate of 26.60% with CMA technique（P=0.004）; the combined detection rate of the two techniques was 28.44%. In 17 cases, karyotype analysis yielded normal results while CMA microarray showed abnormalities with an extra abnormal detection rate of 15.60%. Among the 17 fetuses with chromosomal abnormalities, 6 had micro-deletion, 9 had micro-duplication, 1 had both micro-deletion and micro-duplication, and 1 had heterozygous loss of single parent diploid. Conclusion CMA technique can be used to detect abnormal chromosomal copy numbers in fetuses with cerebral ventriculomegaly to increase the detection rate of chromosomal abnormalities and facilitate prenatal consultation and prognostic evaluation.