Association analysis of single nucleotide polymorphisms in DGAT1, TG and FABP4 genes and intramuscular fat in crossbred Bos taurus cattle.

Previous studies have indicated that single nucleotide polymorphisms (SNPs) in the diacylglycerol-O-acyltransferase1 (DGAT1), thyroglobulin (TG) and adipose fatty acid binding protein (FABP4) genes are associated with intramuscular fat (IMF) levels or marbling scores in beef. The objectives were to estimate the frequency of SNPs in these candidate genes in purebred Irish cattle (n=459) and to determine if individual SNPs are associated with IMF values of longissimus thoracis et lumborum (LTL) and semimembranosus (SM) muscle of crossbred animals (n=138). Results indicated no significant association between the SNPs and IMF, despite the power of this study being sufficient to detect an association with SNPs in the DGAT1 and FABP4 genes. The results confirm the lack of an association found by many other studies and suggest that these SNPs are not influential on the divergent IMF levels in the crossbred population tested.