Clinical exome sequencing for carrier screening in assisted reproductive technology and sperm donation

To assess the efficacy of clinical exome sequencing (CES) in individuals involved in assisted reproductive technology (ART) or sperm donor programs, with a specific focus on its impact on clinical decision-making.

A total of 3991 individuals without a family history of genetic disorders underwent CES targeting 5595 genes at a reproductive center between December 2022 and April 2024. The cohort comprised 217 sperm donors, 232 female recipients, and 1771 couples (3542 patients) undergoing ART with their own gametes. At-risk couples (ARCs) were identified when both partners had a pathogenic or likely pathogenic variant (P/LP) in the same autosomal recessive gene or X-linked variants in females. The analysis primarily examined carrier frequencies, reproductive choices, and outcomes of ARCs.

Among the 3991 individuals screened, 3895 (97.6%) were found to carry at least one P/LP variant, with an average carrier burden of 3.8 variants per individual, showing no significant disparity in carrier status between individuals with infertility and sperm donors/recipients. Within the screened couples, 9.3% were identified as ARCs and 2.3% opted for preimplantation genetic testing for monogenic diseases (PGT-M). As of now, 31 ARCs proceeded with the transfer of euploid and unaffected blastocysts, resulting in 8 healthy live births and 13 ongoing pregnancies.

The findings reveal a significant prevalence of carrier status for autosomal recessive and X-linked diseases, irrespective of fertility status. This highlights the critical importance of integrating genetic risk counseling and informed reproductive decision-making into fertility clinics and sperm banks.