Application of SNP-array in prenatal diagnosis

Abstract

Objective To investigate the clinical value of single nucleotide polymorphism array (SNP-array) and chromosomal microarray analysis in the prenatal diagnosis. Methods A total of 83 pregnant women in Taian Central Hospital from November 2016 to March 2018 were selected, of which the causes of consultation were abnormal hyaline layer of fetal neck, abnormal ultrasonographic structure of fetus, fetal growth retardation and non-invasive DNA screen suggesting high risk. Fetal amniotic fluid or umbilical cord blood was extracted and determined by SNP-array technique and chromosomal microarray analysis for prenatal diagnosis. Results Among 83 fetuses, the detection rate by SNP-array technology was 26.51% (22/83), and it was 22.89% (19/83) by chromosomal microarray analysis. Among them, 25 cases of fetal structural abnormalities were detected by ultrasonography, 11 cases of chromosomal abnormalities were determined by SNP-array technology, and 8 chromosomal abnormalities were checked out by chromosomal microarray analysis. Traditional chromosomal microarray analysis technology revealed a low-proportion chimerism of chromosome 2 (noninvasive DNA suggesting a high risk of trisomy 21), but SNP-array technology did not check out the abnormality. Conclusions Compared with traditional chromosomal microarray analysis, SNP-array technology has obvious advantages and value in detecting fetal chromosome abnormalities. However, traditional chromosomal microarray analysis is still an important diagnostic technology which can’t be ignored. Key words: Prenatal diagnosis; Abnormal fetal development; Chromosomal microarray analysis; Chromosomal karyotyping