A clinical study of CNV-seq techniques in 103 cases of spontaneous abortion

Abstract Objective: To detect the relationship between spontaneous abortion and chromosomal abnormalities by genome copy number variation sequencing (CNV-seq), and explore this relationship’s application to the genetic diagnosis of spontaneous abortion. Methods: From June, 2020 to August, 2022, 103 different embryonic tissue samples from patients who suffered spontaneous abortion in Yueyang Central Hospital were detected by CNV-seq, and the results were analyzed and interpreted after excluding maternal cell contamination. Results: 97 of the 103 cases were detected successfully. A total of 49 cases (50.5%) of abnormal karyotypes were found, including 33 cases of abnormal chromosome number, 12 cases of structural abnormalities (including 14 pathogenic CNVs and 3 variants of uncertain significance,), 3 cases of triploid, and 1 cases of absence of heterozygosity (AOH). The detection rate of chromosomal abnormalities in abortion tissues in the ≥ 35 years old group was higher than that in the <35 years old group (58.8% vs. 48. 7%). Conclusion: Fetal chromosomal abnormalities are an important cause of abortion, CNV-seq technology can efficiently detect chromosomal number abnormalities, large fragment deletions/duplications and pathogenic genome copy number variants, which greatly improves the detection rate of chromosomal abnormalities and provides a valuable genetic risk assessment to couples trying to reproduce again.