Identification of Candidate Genes and Pathways Linked to the Temperament Trait in Sheep

Abstract

Temperament can be defined as the emotional variability among animals of the same species in response to the same stimulus, thus being able to group animals by reactivity as nervous, intermediate or calm. The main objective for this study was to identify genomic regions with the temperament phenotype measured by the Isolation Box Test (IBT) by single-step genome wide association studies (ssGWAS). The database used consisted of 4,317 animals with temperament records, and 1,697 genotyped animals with 38,268 effective SNP after quality control. We identified three genomic regions that explained the greatest percentage of the genetic variance, resulting in 25 SNP associated with candidate genes on chromosomes 6, 10 and 21. A total of nine candidate genes are reported for the temperament trait, which are: PYGM, SYVN1, CAPN1, FADS1, SYT7, GRID2, GPRIN3, EEF1A1 and FRY, linked to energetic activity of the organism, synaptic transmission, meat tenderness and calcium associated activities. This is the first study to identify these genetic variants associated with temperament in sheep, leading the opportinuty to potential applications of these molecular markers in future behavioral research.