ASSOCIATION OF AGPAT6 GENE POLYMORPHISM WITH MILK PRODUCTION TRAITS AND ITS EXPRESSION IN PERIPHERAL BLOOD MONONUCLEAR CELLS OF POSTPARTUM DEONI CATTLE

tAGPAT6 gene, which encodes for the enzyme 1-acylglycerol-3-phosphate O-acyltransferase 6, is a vital component in lipid metabolism and plays a significant role in milk fat production in dairy animals. The present study investigated the association of genetic variation within 5′UTR exons 1-1511, 3′UTR exons 1512-1723 of AGPAT6 gene in Deoni cows with milk production traits using PCR-SSCP method. The present investigation revealed three unique SSCP patterns, ‘1’, ‘2’ and ‘3’ in Exon 1 of the AGPAT6 gene. A total of two novel single nucleotide polymorphisms (SNPs) were identified in the coding region of Exon 1. Both the SNPs were found to cause silent mutation having significant (p≤0.01) association with fat percentage. The present study further aimed to investigate the relative abundance (%) of mRNA of AGPAT6 gene in PBMC of Deoni cows from the day of calving (0th day) to the 60th day post-partum using qRT-PCR. Expression levels of AGPAT6 were significantly elevated (p < .05) on the 30th, 40th, and 60th days postpartum relative to calving day, highlighting its pivotal role in extensive milk fat synthesis during lactation. The variation in expression, with a greater than 10-fold increase from day 0 to day 60, was predominantly driven by the lactation stage. Therefore, enhancing AGPAT6 gene expression in bloodstream signifies a valuable approach for the early identification of cows exhibiting increased milk fat levels and production during lactation. Additionally, the recognized polymorphisms could serve as genetic indicators for selective breeding.