Identification of single nucleotide polymorphisms in carnosine-related genes and effects of genotypes on pork meat quality attributes
D'Astous-Pagé, J., Gariépy, C., Blouin, R., Cliche, S., Méthot, S., Sullivan, B., Fortin, F., Palin, M.F. (2017). Identification of single nucleotide polymorphisms in carnosine-related genes and effects of genotypes on pork meat quality attributes. Meat Science, [online] 134 54-60. http://dx.doi.org/10.1016/j.meatsci.2017.07.019
Plain language summary
Identification of sequence variations in carnosine-related genes and their effects on meat quality attributes in pigs: Carnosine, a molecule formed from only two amino acids, occurs naturally and only is found in meat and some fish. Numerous recent scientific publications have shown that carnosine has several benefits for human health. In addition, its multiple biochemical properties give it preventive and even therapeutic potential. Our research team also observed that pigs with high muscle carnosine levels produced better quality meat that retains more moisture and has a more attractive colour. The results also showed large differences in muscle carnosine levels between pigs, suggesting a possible genetic component.
In order to explain this high variability, the researchers in this study first identified sequence variations in four genes associated with the formation and transport of carnosine in muscle. One of these sequence variations, which is found in a gene (SLC15A4) that allows carnosine to be transported within the muscle cell, is associated with an increase in muscle carnosine content in pigs and better quality meat. This study shows that genetic selection to increase the favourable sequence variation of the SLC15A4 gene could contribute to improving meat quality, particularly in the Yorkshire breed. This advance could improve the nutritional value of an already high-protein food and help the pork sector regain market share.
Carnosine has pH-buffering and antioxidant properties that may bring advantages in terms of meat quality attributes. This study aimed at identifying polymorphisms in carnosine-related genes (CARNS1, SLC6A6, SLC15A3, SLC15A4) that might associate with muscle carnosine content and meat quality traits in pigs (Duroc, Landrace, Yorkshire). Twenty seven SNPs were identified and association analyses performed for SLC15A3 c.*35C > T and c.*52C > T (3′ UTR region), and SLC15A4 c.658A > G (Ile220Val) and c.818G > A (Ser273Asn) SNPs. Associations were observed for SNP c.658A > G with carnosine content, color b* and L*, drip and cooking losses, pH 24 h and glycolytic potential values (P ≤ 0.05). The same associations were observed for SNP c.818G > A, but they were not significant after FDR correction. Results suggest that specific SLC15A4 gene variants might increase muscle carnosine content and improve meat quality. With a minor allele frequency of 0.17 for SNP c.658A > G in Yorkshire pigs, selection in favor of the c.658A allele may be considered as a mean to improve pork quality attributes.