Screening for genomic regions associated to genomic association for reproductive efficiency in the Pura Raza Spanish horse using high density genotyping data

NORA LASECA; SEBASTIÁN DEMYDA-PEYRÁS; DAVINIA PERDOMO-GONZALES; BEGOÑA ESCRIBANO; MERCEDES VALERA; ANTONIO MOLINA ALCALÁ

Davos

Conferencia; 72nd Annual Meeting of the European Federation of Animal Science; 2021

Reproductive traits are a key factor in the economic success of horse production systems. However, they are scarcely analyzed, probably due to the lack of reliable phenotypic data and the difficulty to model the environmental factors. Even less suing genomic approaches and association studies. Among them, the reproductive efficiency (RE), determined as the deviation between optimal and real parity number at age of each mare, was suggested as one of the most promising traits to evaluate individual fertility at the herd and individual level. In this study, we performed a genome-wide association study (GWAS) for RE in a population of 821 Pura Raza Español (PRE) horses. To this, we estimated two RE pseudophenotypes using the pedigree-based matrix (A; determined by DEBVRE) and a hybrid matrix H constructed blending the genomic-relationship matrix (G) (obtained based on XXX SNP MARKERS) with A (ssDEBVRE). The genomic dataset included 148,073 SNP markers from the autosomal chromosomes linkage disequilibrium (LD) and MAF pruning. The GWAS analysis was performed using GEMMA software with a linear model association test. Our results showed that the model based on genomic pseudophenotypes (ssDEBVRE) showed a better adjustment. In addition, we detected 30 genomic regions with a significant association to the RE values. Among them, two regions, located in ECA XX and ECAXX included 3 candidate genes (AKAP3, ATP2B4, ACRBP) involved with sperm motility and capacitation. To our knowledge, this is the first report of GWAS analysis on horse fertility using a large dataset of deregressed data. Further analysis is necessary to validate our findings.