Analysis of copy number variations and possible candidate genes in spontaneous abortion by copy number variation sequencing.

Introduction: Embryonic chromosomal abnormalities represent a major causative factor in early pregnancy loss, highlighting the importance of understanding their role in spontaneous abortion. This study investigates the potential correlation between chromosomal abnormalities and spontaneous abortion using copy number variation sequencing (CNV-seq), a Next-Generation Sequencing (NGS) technology. Methods: We analyzed Copy Number Variations (CNVs) in 395 aborted fetal specimens from spontaneous abortion patients by CNV-seq. And collected correlated data, including maternal age, gestational week, and Body Mass Index (BMI), and analyzed their relationship with the CNVs. Results: Out of the 395 cases, 67.09% of the fetuses had chromosomal abnormalities, including numerical abnormalities, structural abnormalities, and mosaicisms. Maternal age was found to be an important risk factor for fetal chromosomal abnormalities, with the proportion of autosomal trisomy in abnormal karyotypes increasing with maternal age, while polyploidy decreased. The proportion of abnormal karyotypes with mosaic decreased as gestational age increased, while the frequency of polyploidy and sex chromosome monosomy increased. Gene enrichment analysis identified potential miscarriage candidate genes and functions, as well as pathogenic genes and pathways associated with unexplained miscarriage among women aged below or over 35 years old. Based on our study, it can be inferred that there is an association between BMI values and the risk of recurrent miscarriage caused by chromosomal abnormalities. Discussion: Overall, these findings provide important insights into the understanding of spontaneous abortion and have implications for the development of personalized interventions for patients with abnormal karyotypes.

Frequency of HLA­G UTR­1/UTR­3/UTR­7 in women with unexplained recurrent spontaneous abortion.

Human leukocyte antigen (HLA)-G is an important molecule that maintains maternal-fetal interface tolerance and plays a vital role in a healthy pregnancy. Single-nucleotide polymorphisms in the 3'-untranslated regions (UTR) of the HLA-G gene may differ in women with unexplained recurrent spontaneous abortion (URSA). The present study involved the isolation of genome DNA from peripheral blood leukocytes, Sanger sequencing and analysis of the polymorphism sites in the 3'UTR of the HLA-G gene based on polymerase chain reaction. In total, 261 DNA samples from cases of URSA (n=133), including primary URSA (n=83) and secondary URSA (n=50), and controls (n=128) were evaluated. The present data showed that +3010CC genotype carriers exhibited a higher risk of URSA, while +3187GG genotype carriers exhibited a lower risk. Secondary URSA patients carrying +3010C had a higher risk of URSA, while +3187G carriers exhibited a lower risk of URSA. UTR-1 haplotype carriers may be associated with a reduced risk of primary and secondary URSA. Notably, UTR-3 and UTR-7 could increase the risk of primary and secondary URSA, respectively. The present results showed that HLA-G 3'UTR polymorphisms and haplotypes may be involved in URSA development and be a predictor of pregnancy outcome.