亲子鉴定实验用于评估产前诊断中母体细胞污染的研究

Application of paternity test in prenatal diagnosis of maternal cell contamination assessment

目的探讨亲子鉴定实验在产前诊断母体细胞污染(MCC)评估中的临床应用价值。方法选取2005-2019年来该院行产前诊断的134个单基因遗传病高风险家系的137例孕妇。于超声监视下行羊膜穿刺术,抽取羊水,提取羊水细胞基因组DNA。对羊水细胞基因组DNA、胎儿父母亲基因组DNA作亲子鉴定实验。采用多重荧光PCR技术扩增基因组DNA的15个短串联重复序列(STR)位点。根据分型结果判断是否存在MCC,以及MCC的程度。结果亲子鉴定实验结果显示,男性胎儿76例,女性胎儿61例,均未发现MCC;其中证实先证者为新发突变4例,占高风险家系的3.0%。所检测的胎儿特定遗传病基因型异常的有35例,占25.6%(35/137);回访121例,出生(引产)后的检查结果与产前诊断结果完全一致。结论基于多重荧光PCR技术的亲子鉴定实验可提示母体细胞对羊水细胞基因组DNA污染程度,确定胎儿的独立个体身份和性别,对提高产前诊断的准确性有重要意义。

Objective To explore the clinical value of paternity test in prenatal diagnosis of maternal cell contamination(MCC)assessment.Methods From 2005 to 2019,137 pregnant women from 134 families with high-risk specific monogenetic disease received prenatal diagnosis in the hospital were selected.Amniocentesis was performed under ultrasonic surveillance,amniotic fluid was extracted,and genomic DNA of amniotic fluid cells was isolated.Fifteen short tandem repeats(STR)loci of genomic DNA were amplified by multiple fluorescence PCR.The existence of MCC and the degree of MCC were determined according to the genotyping results.Results The paternity test results showed that there were 76 male fetuses and 61 female fetuses,and no MCC was found.Among them,4 cases(3.0%)of new mutation were confirmed as proband.Thirty-five cases[25.6%(35/137)]of fetal specific genetic disease genotype abnormalities were detected.The results of the examination after birth(induced labor)were consistent with the results of prenatal diagnosis.Conclusion Paternity test based on multiple fluorescent PCR technology could evaluate the MCC of amniotic fluid genomic DNA,and determine the individual identity and gender of the fetus.Therefore,paternity testing plays an important role in determining the diagnostic accuracy during prenatal diagnosis.