基于游离DNA单分子标签检测技术的苯丙酮尿症无创产前检测:4例分析  

Cell-free DNA barcode-enabled single-molecule test for non-invasive prenatal diagnosis of phenylketonuria:an analysis of four cases

作　　者：夏俊珂 代鹏[1] 王晓锋 赵干业 刘宁[1] 孔祥东[1] Xia Junke;Dai Peng;Wang Xiaofeng;Zhao Ganye;Liu Ning;Kong Xiangdong(Department of Obstetrics and Gynecology,Genetics and Prenatal Diagnosis Center,the First Affiliated Hospital of Zhengzhou University,Zhengzhou 450052,China;Genetalks Biotech Inc.,Changsha 410152,China)

机构地区：[1]郑州大学第一附属医院妇产科遗传与产前诊断中心,450052 [2]人和未来生物科技(长沙)有限公司,410152

出　　处：《中华围产医学杂志》2021年第2期126-130,共5页Chinese Journal of Perinatal Medicine

基　　金：国家重点研发计划(2018YFC1002206-2)。

摘　　要：目的研究游离DNA单分子标签检测(cell-free DNA barcode-enabled single-molecule test,cfBEST)技术用于苯丙酮尿症(phenylketonuria,PKU)无创产前诊断的适用性和可行性。方法研究对象为2019年7月至9月郑州大学第一附属医院进行产前诊断的4例诊断为PAH基因热点突变的苯丙酮尿症家系。采用cfBEST技术进行检测,设计巢式聚合酶链反应引物,计算孕妇血浆游离DNA突变频率和胎儿基因型,并将cfBEST技术的检测结果与介入性产前诊断结果比较。对数据采用描述性统计分析。结果cfBEST技术检测发现,家系1中c.603T>G和c.842+2T>A位点的突变频率为48.40%(291/601)和9.70%(61/628),胎儿2个位点均为杂合突变型,为PKU患者。家系2中c.1238G>C和c.842+2T>A的突变频率分别为43.70%(786/1798)和0%(0/1550),胎儿2个位点均为野生型,非PKU患者,亦非携带者。家系3中,c.1045T>G和c.728G>A的突变频率分别为44.00%(930/2112)和0%(0/705),胎儿2个位点均为野生型,非PKU患者,亦非携带者。家系4中,c.755G>A和c.728G>A的突变频率分别为45.40%(743/1637)和4.50%(28/849),胎儿位点分别为野生型和杂合突变型,为携带者。介入性产前诊断结果与cfBEST技术检测结果完全一致。家系1选择引产,其余3个家系选择继续妊娠至足月分娩,其新生儿筛查苯丙氨酸水平均<120μmol/L,生后1、3、6月龄电话随访,均未见明显异常。结论cfBEST技术有望应用于PKU PAH基因的无创产前诊断,但需要更大样本量的研究证实。Objective To analyze the applicability and feasibility of a cell-free DNA barcode-enabled single-molecule test(cfBEST)in non-invasive prenatal diagnosis of phenylketonuria.Methods This study recruited four pregnant women who were prenatally diagnosed as heterozygous carriers of hot spot mutations in the PAH gene from pedigrees with phenylketonuria at the First Affiliated Hospital of Zhengzhou University from July to September 2019.The frequency of mutations in maternal plasma cell-free DNA and the fetuses'genotypes were analyzed by cfBEST.Nested polymerase chain reaction primers were designed to amplify the mutation sites in each pedigree.The results of cfBEST were compared with those of invasive prenatal diagnosis.Descriptive analysis was used for data analysis.Results In pedigree 1,the frequency of c.603T>G and c.842+2T>A mutations in maternal plasma cell-free DNA were 48.40%(291/601)and 9.70%(61/628),which was detected by cfBEST.The fetus was diagnosed with phenylketonuria with two heterozygous mutations.In pedigree 2,the frequency of c.1238G>C and c.842+2T>A mutations in maternal plasma cell-free DNA was 43.70%(786/1798)and 0%(0/1550),respectively.Both mutations were wild-type,and the fetus was neither phenylketonuria nor a carrier.In pedigree 3,the frequency of c.1045T>G and c.728G>A mutations in maternal plasma cell-free DNA was 44.00%(930/2112)and 0%(0/705),respectively,suggesting that both mutations in the fetus were wild-type,and the fetus was neither phenylketonuria nor a carrier.In pedigree 4,the frequency of c.755G>A and c.728G>A mutations were 45.40%(743/1637)and 4.50%(28/849),respectively,which indicated that the former was wild-type,and the latter was heterozygous;namely the fetus was a carrier of phenylketonuria.The results of cfBEST were consistent with those of invasive prenatal diagnosis.Three pedigrees(Pedigree 2,3 and 4)continued the pregnancy to full-term,and the phenylalanine levels in the neonates were all below 120μmol/L.No abnormalities were reported in those three infants during follow

关 键 词：苯丙酮尿症 苯丙氨酸羟化酶 非侵入性产前检测 

分 类 号：R714.5[医药卫生—妇产科学]