Association analysis between FASN genotype and milk traits in Mediterranean buffalo and its expression among different buffalo tissues

Abstract

Fatty acid synthase (FASN) is a multifunctional protein that catalyzes the synthesis of long-chain saturated fatty acid. In this study, we identified the single nucleotide polymorphisms (SNPs), and their association with milk traits in Mediterranean buffalo, and the expression of FASN gene in different tissues was measured. Nine SNPs (g.-1640G > A, g.-1099C > T, g.1095C > A, g.3221G > A, g.4762G > A, g.5299G > A, g.7164G > A, g.7272T > C, and g.8927T > C) were identified by DNA pooled sequencing and then genotyped. Seven identified SNPs except g.3221G > A and g.8927T > C were found significantly associated with both fat and protein percentage, and also the g.7164G > A and g.8927T > C had significant association with peak milk yield and protein percentage, respectively. One haplotype block was successfully constructed by linkage disequilibrium (LD) analysis and it showed a significant association with both fat percentage and protein percentage. Expression of FASN gene was found in almost all the buffalo tissues including mammary gland, heart, liver, spleen, lung, kidney, uterus, and ovary, and to be highest in lung and mammary gland. Our findings suggest that polymorphisms in the buffalo FASN gene are associated with milk production traits and can be used as a candidate gene for milk traits and marker-assisted selection in buffalo breeding program.