单核苷酸多态性微阵列技术在胎儿颈部淋巴水囊瘤产前诊断中的应用研究

Application of single nucleotide polymorphism array in prenatal diagnosis of fetal cervical cystic hygroma

目的 探讨单核苷酸多态性微阵列技术(single nucleotide polymorphism array, SNP array)在胎儿颈部淋巴水囊瘤(cervical cystic hygroma, CCH)产前诊断中的应用价值。方法 收集2019年1月至2021年5月在广西壮族自治区妇幼保健院经超声诊断为CCH的170例胎儿,应用SNP array检测染色体拷贝数变异(copy number variation, CNV),采用G显带进行染色体核型分析。结果 综合染色体核型分析和SNP array检测结果,在170例CCH胎儿中,71例检测到染色体异常(41.8%):特纳综合征最多(15.98%,27/170)、其次为21-三体综合征(10%,18/170)、18-三体综合征(7.1%,12/170)、13-三体综合征(0.6%,1/170)、47,XXX综合征(0.6%,1/170)和15-三体的嵌合(0.6%,1/170)。SNP array在12例胎儿中检出CNV(7.1%,12/170),其中10例致病性CNV,2例临床意义不明CNV。在细胞培养失败和染色体核型分析结果正常的CCH胎儿中,SNP array分别检出2例和8例染色体异常。结论 胎儿CCH与染色体异常相关,以染色体非整倍体为主,但也存在CNV、易位等染色体异常。因此,针对B超诊断为CCH的胎儿,同时进行染色体核型分析和SNP array检测,可以为胎儿CCH的遗传咨询和预后评估提供更为精准的信息和依据。

Objective To investigate the clinical value of single nucleotide polymorphism array(SNP array) in the prenatal diagnosis of fetal cervical cystic hygroma(CCH).Methods From January 2019 to May 2021,a total of 170 fetuses with CCH which were diagnosed by B-ultrasonography were enrolled.The chromosome copy number variation(CNV) was detected by SNP array, and the chromosome karyotype was analyzed by G-banding.Results Combine the results of karyotyping and SNP-array, 71 fetues with chromosomal abnormalities(41.8%) were dectected in the 170 fetuses with CCH:Turner’s syndrome was the most common(15.98%,27/170),followed by 21 trisomy(10%,18/170),18 trisomy(7.1%,12/170),13 trisomy(0.6%,1/170),47,XXX syndrome(0.6%,1/170) and 15 trisomy mosaicism(0.6%,1/170).SNP array detected 12 cases with abnormal CNV(7.1%,12/170),of which 10 cases were pathogenic CNV and 2 cases were uncertain significance CNV.In CCH fetuses with failed cell culture and normal karyotype analysis, SNP array detected chromosome abnormalities in 2 cases and 8 cases respectively.Conclusion Fetal CCH is associated with chromosomal abnormalities, mainly chromosomal aneuploidy, but there are also chromosomal abnormalities such as CNV and translocation.Therefore, for fetuses diagnosed as CCH by B-ultrasound, karyotype analysis and SNP array detection can provide more accurate information and basis for the genetic counseling and prognosis evaluation of fetal CCH.