胎儿染色体非整倍体疾病中产前无创基因检测的诊断价值

Diagnostic value of prenatal noninvasive gene detection in fetal chromosomal aneuploidy

目的探讨并分析无创基因检测在诊断胎儿染色体非整倍体疾病中的临床诊断和应用价值。方法选取我院2016年1月-2017年6月期间于我院产科接受产前检查的孕妇为研究对象。根据孕妇的血清学筛查结果、B超检查结果和孕妇年龄,筛查出需要接受外周血中游离胎儿DNA检测的孕妇,最终150例高危孕妇接受外周静脉血无创基因检查。按照年龄和血清学检查结果,将患者分为高危组,高龄组和其他原因组,对检查结果提示高风险的孕妇转诊进行羊水细胞染色体核型分析,对检查结果提示低风险的患者进行电话随访。结果 3组孕妇共计150例接受无创DNA检测,检查结构异常者8例,其中高危组4例,占比6.45%,包括21-三体2例,13-三体1例,性染色体异常1例;高龄组3例,占比5.26%,包括21-三体1例,18-三体1例,性染色体异常1例;其他原因组1例,为21-三体。8例检查结果异常者,7例孕妇进一步接受羊水细胞染色体核型分析,1例无创DNA检测结果提示为21-三体的孕妇放弃进一步检查。3例提示21-三体高风险孕妇染色体核型分析结果具体为,1例染色体核型为46,XN;2例染色体核型为47,XN,+21。1例13-三体高风险孕妇染色体核型分析结果为47,XN,+13。1例18-三体高风险孕妇染色体核型分析结果为47,XN,+21。结论无创DNA检测对染色体非整倍体的检出率高,但存在一定的假阳性,在临床工作中可结合多种产前检查手段,对患者进行综合筛查,对预防降低出生缺陷有重要的临床意义。

Objective:To explore and analyze the clinical diagnosis and application value of noninvasive gene detection in the diagnosis of fetal chromosomal aneuploidy.Methods:In our hospital from January 2016 to June 2017,the pregnant women who received prenatal examination in our department of gynecology and obstetrics were studied.According to the serological screening results of pregnant women,B-ultrasound examination results and the age of pregnant women,we screened the pregnant women who need to detect the free fetal DNA in the peripheral blood.Finally,150 high-risk pregnant women received noninvasive genetic examination of peripheral venous blood.According to the age and serological examination results,the patients were divided into high-risk group,elderly group and other reasons group.Results:A total of 150 pregnant women in three groups received noninvasive DNA test,and 8 cases had abnormal structure.Among them,4 cases were high-risk group,accounted for 6.45%,included 2 cases of 21-trisomy,1 case of 13-trisomy,1 case of sex chromosome abnormalities.There were 3 cases in the elderly group,accounted for 5.26%,included 1 case of 21-trisomy,1 case of 18-trisomy,and 1 case of sex chromosome abnormality.1 case of other causes were 21-trisomy.8 cases of abnormal examination results,7 cases of pregnant women further accepted the karyotype analysis of amniotic fluid cells,1 case of non-invasive DNA test results indicated that 21-trisomy pregnant women to give up further examination.The results of chromosome karyotype analysis in 3 cases of high risk pregnant women with 21-trisomy were specific,1 case of chromosome karyotype were 46,XN;The karyotypes of 2 cases were 47,XN,and+21.The results of chromosome karyotype analysis in 1 case of high risk pregnant women with 13-trisomy were 47,XN,+13.The results of chromosome karyotype analysis in 1 case of high risk pregnant women with 18-trisomy were 47,XN,+21.Conclusion:Noninvasive DNA detection has a high detection rate for chromosomal aneuploidy,but it has some false positives.It can combine multiple prenatal examination methods in clinical work to make comprehensive screening for patients,which has important clinical significance for preventing birth defects.