Comparison of PRKAG3 and RYR1 gene effect on carcass traits and meat quality in Slovenian commercial pigs

The effect of polymorphisms at PRKAG3 (R200Q and I199V) and RYR1 (R615C) genes on carcass traits and meat quality was examined in a sample of 257 commercial pigs, crosses of Landrace x Large White as maternal line and Pietrain (N = 96), Pietrain x Landrace (N = 42) or Pietrain x Hampshire (N = 119) as paternal line. Pigs were genotyped (PCR-RFLP) and traits of interest were measured (which included carcass and ham weight, measurements of fatness, meatiness, ultimate pH, colour parameters and drip loss). The observed genotype frequencies at PRKAG3 gene were 9.7%, 38.9%, 32.7%, 6.2% and 12.5% for R/R-I/I, R/R-I/V, R/R-V/V, Q/R-I/V and Q/R-V/V genotype, respectively. RYR1 genotype frequencies were 57.2% for N/N and 42.8% for N/n genotype. Studied polymorphisms exhibited a significant effect on meat quality, but mainly an insignificant effect on carcass traits. No significant interaction between PRKAG3 and RYR1 was found. Carriers of RYR1 mutant allele "n" had less intense longissimus dorsi muscle colour (subjective score, Minolta L* and b*) and higher drip loss. Regarding PRKAG3, the ultimate pH decreased and Minolta L*, a*, b* and drip loss increased in the following order: R/R-I/I, R/R-I/V, R/R-V/V, Q/R-I/V and Q/R-V/V, according to the presence of 199I and absence of 200Q alleles. The study shows that the I199V polymorphism is an important source of variation in pigs free of 200Q. In particular the 199I proves beneficial for meat quality. The results of combining the RYR1 and PRKAG3 genotypes indicate that R/R-I/I genotype could be used in counterbalancing the negative effects of "n" allele on meat quality.