Association between PON1 Gene SNPs and Growth and Carcass Traits in Beef Cattle

Paraoxonase-1 (PON1), like lipoprotein lipase (LPL), plays a key role in the metabolism and physiology of mammalian growth. The objectives of this study were to estimate the allele and genotype frequencies at the PON1/EcoRV and PON1/AluI loci in three genetic groups of beef cattle and to determine associations between these polymorphisms and growth and carcass traits. Genotyping was performed on 30 Angus, 32 Hereford and 26 Simmental. The association analysis was carried out using the GLM procedure of SAS 9.1 and the least squares means of the genotypes were compared by the Tukey's test. Animals with AG genotype at the PON1/EcoRV locus had higher weight at the time of entry into the fattening corrals ($329.97{\pm}6.08kg$) and close to the time of slaughter ($577.56{\pm}8.32kg$) and net meat weight ($275.89{\pm}4.05kg$) and fitted tenderness ($3.10{\pm}0.19kg$) (p<0.05). Animals with AA genotype at the PON1/AluI locus had higher weight at the time of entry ($333.37{\pm}8.93kg$) and slaughter ($576.82{\pm}13.18kg$) and net meat weight ($275.49{\pm}6.43kg$) and average daily gain ($0.68{\pm}0.02kg/d$) (p<0.05). The meat color score was also significantly higher (p<0.05). Between genotypes and breeds, there were significant differences observed except for TBW, REMG, MBS, REA and MCS. As a metabolism gene, genotypes of the SNPs of PON1 gene might be reflecting BFT directly, such as $A_eA_eG_aG_a$ genotype in this experiment.