Analysis of Clinical Application Value of Expanded Non-invasive Prenatal Tes-ting for Screening Fetal Chromosome Copy Number Variations
- VernacularTitle:扩展型无创产前检测筛查胎儿染色体拷贝数变异的临床应用价值分析
- Author:
Le ZHANG
1
;
Jie WEI
1
;
Jinhua ZHANG
1
;
Lixia WANG
1
;
Huijun LI
1
;
Shuyuan XUE
1
Author Information
1. 乌鲁木齐市妇幼保健院医学遗传中心 新疆围产期疾病临床医学研究中心,新疆乌鲁木齐 830001
- Publication Type:Journal Article
- Keywords:
Expanded non-invasive prenatal testing;
Copy number variant;
Chromosome microarray analysis;
Regions of Homozygosity
- From:
Journal of Practical Obstetrics and Gynecology
2025;41(6):514-519
- CountryChina
- Language:Chinese
-
Abstract:
Objective:To investigate the clinical application value of expanded non-invasive prenatal testing(NIPT-plus)in screening for fetal chromosome copy number variations(CNV).Methods:From January 2021 to December 2023,141 pregnant women who voluntarily underwent amniocentesis at the Prenatal Diagnostic Centre of Urumqi Maternal and Child Health Hospital due to NIPT-plus suggesting a high risk of fetal CNV were selected.Amniotic fluid samples were collected for fetal chromosome karyotyping and chromosome microarray analysis(CMA).Pregnant women who underwent the above tests signed an informed consent form,and all cases were followed up forpregnancy outcome.Results:Among 141 NIPT-plus screen positive pregnant women,41 true posi-tive cases were detected by chromosomal karyotype analysis and CMA.The positive predictive value(PPV)for NIPT-plus screening for CNV was 29.08％(41/141).There was no statistically significant difference(P＞0.05)in the PPV of CNV detected by NIPT plus among different ages,indications and variant types.However,the PPV of CNV size＜10 Mb was significantly higher than that of CNV size≥ 10 Mb,and the difference was statistically signif-icant(39.62％vs.22.73％,P＜0.05).Among the 41 true positive cases,in addition to CNV,the CMA also detec-ted 7 cases of regions of Homozygosity(ROH),accounting for 17.07％(7/41)of the cases,two of which involved imprinted genes located on chromosomes 6 and 7.All continued pregnancy after genetic counselling and no signif-icant abnormalities were seen at neonatal follow-up after birth.Conclusions:NIPT-plus screening for fetal CNV has some clinical value,especially for CNV with fragment size＜10Mb,but accuracy needs to be further improved;CMA as a molecular diagnostic technique can detect ROH in cases where NIPT-plus suggests CNV abnormali-ties,and the combined use of the two techniques also opens new avenues for screening and diagnosis of prenatal imprinted diseases.
