Comparison of results of prenatal diagnosis by different techniques for fetuses with increased nuchal translucency.
10.3760/cma.j.cn511374-20201015-00721
- Author:
Wencheng DAI
1
;
Xinhong LIU
;
Xiaorong MA
;
Zhen YU
;
Huijun LI
Author Information
1. Urumqi Maternal and Child Health Care Hospital, Urumqi, Xinjiang 830001, China. 38448792@qq.com.
- Publication Type:Journal Article
- MeSH:
Pregnancy;
Humans;
Female;
Adult;
Infant;
Nuchal Translucency Measurement/methods*;
Prenatal Diagnosis/methods*;
Chromosome Aberrations;
Aneuploidy;
Fetus/diagnostic imaging*;
Ultrasonography, Prenatal;
DNA Copy Number Variations;
Transcription Factors
- From:
Chinese Journal of Medical Genetics
2023;40(5):532-537
- CountryChina
- Language:Chinese
-
Abstract:
OBJECTIVE:To assess the value of chromosomal microarray analysis (CMA) and trio-whole exome sequencing (trio-WES) for fetuses with increased nuchal translucency (NT) thickness.
METHODS:Sixty two pregnant women who had visited Urumqi Maternal and Child Care Health Hospital between June 2018 and June 2020 for NT ≥ 3.0 mm at 11 ~ 13+6 gestational weeks were selected as study subjects. Relevant clinical data were collected. The patients were divided into 3.0 ~ ＜3.5 mm (n = 33) and ≥3.5 mm groups (n = 29). Chromosome karyotyping analysis and chromosomal microarray analysis were carried out. And trio-WES analysis was performed on 15 samples with NT thickening but negative CMA results. The distribution and incidence of chromosomal abnormalities in the two groups were compared by using chi-square test.
RESULTS:The median age of the pregnant women was 29 years old (22 ~ 41 years old), the median thickness of NT was 3.4 mm (3.0 ~ 9.1 mm), and the median gestational age at the detection was 13+4 weeks (11+5 ~ 13+6 weeks). Chromosome karyotyping analysis has detected 12 cases of aneuploidies and 1 case of derivative chromosome. The detection rate was 20.97% (13/62). CMA has detected 12 cases of aneuploidies, 1 case of pathogenic CNV and 5 cases of variant of uncertain significance (VUS), with a detection rate of 29.03% (18/62). The aneuploidy rate for the NT ≥ 3.5 mm group was higher than that for the 3.0 ≤ NT < 3.5 mm group [3.03% (1/33) vs. 41.38% (12/29), χ² = 13.698, P < 0.001]. There was no statistically significant difference between the two groups in the detection rate of fetal pathogenic CNV and VUS (χ² = 0.028, P > 0.05). Trio-WES analysis of 15 samples with negative CMA result and no structural abnormality has identified 6 heterozygous variants, including SOS1: c.3542C>T (p.A1181V) and c.3817C>G (p.L1273V), COL2A1: c.436C>T (p.P146S) and c.3700G>A (p.D1234N), LZTR1: c.1496T>C (p.V499A), and BRAF: c.64G>A (p.D22N), respectively. Based on the guidelines from the American College of Medical Genetics and Genomics (ACMG), all of the variants were rated as VUS.
CONCLUSION:NT thickening can indicate chromosome abnormality, and CMA and trio-WES may be used for the prenatal diagnosis.
