Genome-wide association studies for growth traits in buffaloes using the single step genomic BLUP

Abstract

Growth traits are important for the profitability of buffalo breeding systems, since in general, these animals are raised both for meat and milk. In this study, the single-step genomic BLUP method was employed to prospect the genomic regions' associated with weight at standard ages of 100, 210, 365, and 550 days in a buffalo population, aiming to identify genes with stronger expression for those characteristics. We found 6, 1, 2, and 5 SNPs significantly associated (p value < 10(-5)) with weight at 100, 210, 365, and 550 days of age, respectively, where those SNPs respectively explained 0.164, 0.040, 0.044, and 0.213% of the additive variance of each trait. SNP AX-85099682 (BBU24) was significant for weight at 100, 210, and 365 days, indicating the existence of a possible QTL affecting the initial growth rate of buffaloes. All told, eight genes (CBLB, TRNAG-UCC, GADD45B, LOC112583811, MGAT4C, KCNMA1, SLC5A2, and TGFB1I1) were identified as candidates for the growth traits of buffaloes. However, molecular and gene expression studies are necessary to validate these genes for subsequent use in programs for genetic improvement of the species.