Genome-wide association study reveals candidate genes for traits related to meat quality in Colombian Creole hair sheep.

Genome-wide association studies (GWAS) allow identifying genomic regions related to traits of economic importance in animals of zootechnical interest. The objective of this research was to conduct a genome-wide association study on meat quality traits using the Illumina OvineSNPs50 BeadChip array. The animals were sampled in the departments of Córdoba, Cesar, and Valle del Cauca. The genotypes obtained with the Illumina OvineSNP50 BeadChip microarray were analyzed SNP (single-nucleotide polymorphism) data to conduct a GWAS for pH and water-holding capacity (WHC) traits measured after 7 days of maturation, in the Longissimus dorsi (LD) muscle, in 167 Creole hair sheep of 12 months old belonging to Pelibuey (CHSP, n = 60), Ethiopian (CHSE, n = 44), and Sudan (CHSS, n = 63) breeds. The GWAS was done using a mixed linear model (MLMA) and based on the Ovis aries v3.1 genome. The CHSE showed the lowest meat juice release and, consequently, the highest water-holding capacity (WHC = 30.6 ± 0.1), suggesting that this breed has better performance in the meat industry compared with CHSS (WHC = 41.7 ± 0.1) and CHSP (WHC = 36.8 ± 0.1), since there is a relationship between WHC and juiciness. For the character pH, it was not possible to annotate genes related to meat quality, while, for the WHC, they have obtained 11 candidate genes associated (ELOVL2, ARAP2, LOC101102527, SHOC2, AIPL1, CSRNP3, IFRD, KDM8, NANS, DAPK1, IBN2, TPM2). Particularly, ELOVL2, ARAP2, IBN2, and TPM2 genes are involved in muscle contraction and fatty acid composition in sheep. In this study, we generated a baseline for GWAS related to meat quality traits in Colombian Creole hair sheep that can be used for future genomic selection plans.

New Insight into the Genome-Wide Diversity and Admixture of Six Colombian Sheep Populations.

Creole sheep represent a strategic genetic resource for populations living in marginal areas under financial restrictions on the American continent. Six Colombian sheep breeds (two wool (BCL-Boyacá and NCL-Nariño, 12 and 14 samples) and four hair (OPCE-Ethiopian, 54 samples; OPCS-Sudan, 74 samples; OPCP-Pelibeuy, 59 samples; OPCW-Wayúu, 24 samples) were genotyped using the Illumina Ovine SNP50 BeadChip. Data was also included from international 44 breeds from International Sheep Genomics Consortium (ISGC) and from data published in previous a previous work on the Caribbean and African breeds. Although geographically separated, wool (NCL, BCL) and hair types (OPCE, OPCS, OPCW) presented little genetic differentiation (FST 0.05) at a global level but several groups of animals separated suggesting local clustering due to geographical isolation. The OPCP underwent a recent crossing with Mexican Pelibuey, explaining its differentiation. Findings in this work such as the proximity to West African Djallonké (WAD) and Barbados Black Belly (BBB), suggest different introductions of African type animals from the Caribbean region on a pre-existing genetic basis formed by animals deriving from the first importations coming from Europe in colonial times. As expected, Colombian wool breeds showed, in particular in Admixture software results, a greater genomic component in common with European breeds and in particular with Iberian ones (Churra). This study provides a basis for future research into the genetic diversity within and between the Colombian sheep breeds analysed, and scientific data for policy decisions on Farm Animal Genetic Resources (FAnGR).