Screening 52 single nucleotide polymorphisms for extreme value of glycolytic potential and drip loss in pigs

Abstract

Summary Low heritability of meat quality traits and the lack of their systematic registration in breeding programs have encouraged the search for single nucleotide polymorphisms (SNPs) located within genes coding the proteins involved in muscle and fat metabolism. In this report, a panel of 52 SNPs was used to find which alleles and genotypes are more/less frequent in groups of pigs differentiated by extreme value of glycolytic potential (GP) and drip loss (DL). The analysis was carried out in 52 fatteners (chosen from 246 pigs), of which 28 were Landrace and 27 Landrace x Yorkshire. Two designs were performed: I, fatteners were divided into two groups showing extreme value of GP (<125 versus >145), II, fatteners were divided into two groups showing extreme value of DL (<6.0 versus >6.0). Allele frequency differences between the phenotypic groups of extreme GL or DL were not influenced by the breed. The frequency of 52 SNPs alleles for each of group was calculated and a chi-squared test was used to estimate the significance of differences in allele frequencies between alternative groups in each experimental design. Three SNPs (DECR1, PPARGC1, MC4R) and another two (CYP21, SFRS1) showed significant differences between groups of extreme GP and DL, respectively. To exemplify and validate potential associations of candidate SNPs for GP and DL, 293 fatteners representing three commercial breeds/crosses (95 Landrace, 66 Landrace x Yorkshire and 132 Landrace x Yorkshire x Duroc were genotyped for DECR1 and CYP21 by PCR-RFLP assays. DECR1 showed significant associations with GP in Landrace and Landrace x Yorkshire x Duroc fatteners. CYP21 showed significant associations with DL in all breeds/crosses. Interestingly, the CYP21 polymorphism revealed adverse associations trend in Landrace x Yorkshire x Duroc pigs in comparison to Landrace and Landrace x Yorkshire fatteners.

Technological and sensory pork quality in relation to muscle and drip loss protein profiles

“…The average GP values reported by these authors for each of the three possible genotypes were similar to those obtained in this study. Moreover, Kamiński et al [34] reported the effect of the DECR1 on GP, glycogen metabolism, and meat quality and the reported values of these parameters were similar to those obtained in the present study. DECR1 is a nuclear gene encoded by a mitochondrial enzyme that participates in the fatty acid beta-oxidation pathway.…”

“…Despite that the pigs originated from herds belonging to the program of elimination of disadvantageous genes' influence on meat quality (RYR1 T and RN -), approximately 10 % of the 75 meat samples were classified as PSE and a similar percentage was found for acid meat. However, PSE meat and meat with low pH levels have been observed in races lacking these two genes [17,19,34,35], which may have been due to stress conditions of preslaughter trade, slaughter, and feeding [19,36]. The electrical low voltage stunning may contribute to the occurrence of PSE meat [37,38].…”

Genomics of Fruit Quality and Disorders

“…Other genes for which associations with pH Downloaded by [McGill University] at 09:24 13 June 2016 have been reported include myogenin ), PKM2 , and troponin I (Yang et al 2010). PKM2 and CYP21 are associated with drip loss and DECR1 has been associated with glycolytic potential (Kaminski et al 2010). …”

Expression level of the cytochrome P450c21 (CYP21) protein correlating to drip loss in pigs

“…Stress reactions before the slaughter procedure influences ante-and post-mortem muscle metabolism. Its polymorphism discovered by bioinformatics approach is localized in the putative intron splicing site suggesting possible influence on messenger RNA (mRNA) stability and CYP21 biosynthesis efficiency (Kami nski et al 2010). In pigs, high preslaughter stress led to increasing plasma cortisol levels.…”