Preimplantation genetic testing in equine test-tube embryos: the advent of a new era in breeding champion horses

The high individual value of the horse results in an exponential increase in the number of in vitro produced (IVP) equine embryos. Yet, preimplantation genetic testing (PGT), involving the prelevation of cells from the embryo for genetic profiling prior to embryo transfer, is still limited to sex determination and the detection of a few monogenic traits, using multiplex PCR with variable results. The goal of this project is to develop a generic method for genome-wide concurrent analysis of aneuploidies, monogenic and polygenic traits through genotyping-by-sequencing (GBS) in the horse. We will first optimize the biopsy procedure and implement the GBS algorithm for the horse. This pipeline will be further adapted to improve practical applicability. The ultimate aim is to provide PGT in a clinical context for equine IVP embryos produced in our clinic, using the established method. Finally, the proof-of-concept of equine PGT in a clinical setting holds potential for further valorization.