An Association Study of Meat Eating Quality and Long-chain Fatty Acid Content in Australian Lamb

In sheep and other livestock species, the calpain/calpastatin system is one of the principle genetic influences on variation in meat tenderisation.  Genome wide association studies have shown there is a strong relationship between SNPs located in the fatty acid desaturases locus (i.e. FADS 1/2/3), ELOVL2 and SLC26A10 genes and omega-3 polyunsaturated fatty acid (PUFA) levels in human plasma.  This study determined the genomic association of 182 SNPs specifically selected in genes affecting meat tenderness and the omega-3 PUFAs in Australian lamb.  An additional 10 SNPs from the OvineSNP50 array were selected for inclusion onto a 192 Meat Quality Research (MQR) SNP panel based on their significant genomic association with omega-3 PUFA levels. One-thousand and fifty-eight animals genotyped for this panel had OvineSNP50 array genotypes.  These were used to impute the 192 MQR SNP into 2833 animals with only OvineSNP50 genotypes and hot carcass weight (HCWT) phenotype data using Beagle.  This yielded 3891 genotyped animals for the association study of 192 SNP.  Nine significant SNP associations (P < 0.001) were identified for shear force at day 5, increasing heritability by 2.2%.  Four significant SNP associations (P < 0.001) were identified for intra muscular fat (IMF) percentage. Four and 3 SNPs of the 10 SNPs selected from the OvineSNP50 array were significant at P < 0.001 for EPA+DPA+DHA and EPA+DHA concentration in lamb meat, respectively.