Application of high-throughput whole genome sequencing and STR typing for the analysis of chorea villus tissue samples from spontaneous abortion

Abstract

To apply high-throughput whole genome sequencing (WGS) and short tandem repeat (STR) typing to detect aneuploidies, heteroploidies and copy number variations(CNVs) in spontaneous abortic tissues. Chorionic villus samples from 145 patients with spontaneous abortion were subjected to detection of aneuploidies, heteroploidies and copy number variations by WGS and STR typing. All testing was successful and the rate of chromosomal abnormalities among the patients was 22.07%. Among these, there were 11 trisomies, 3 monosomies, 2 triploidies, 5 autosomal mosaicisms, 4 sex chromosomal mosaicisms, 7 structural abnormalities (including 1 mosaicism). In 89 cases, there were 130 CNVs of uncertain significance, 47 likely benign CNVs, and 2 loss of one copy of pathogenic AR gene. One sample contained 6 fragment duplications and deletions. Only 24 samples had no abnormal finding. The most important reason for spontaneous abortions is embryonic chromosomal abnormality. Combined STR typing and WGS is both comprehensive and fast, and may become a major means for the detection of chorionic villi tissue from spontaneous abortions.