Single Nucleotide Polymorphisms of Leptin and Calpain/Calpastatin in Key Traits of Pork Meat Quality

The increasing demand for food to meet the needs of the planet's growing population requires, among other factors, greater and improved meat production. Meat quality is determined by key consumer-preferred traits, particularly tenderness, juiciness, and flavor. Recently, interest has grown in analyzing the genes associated with these phenotypic characteristics. Single-nucleotide polymorphisms (SNPs) are common genomic variations in cattle and represent the most widely used molecular markers. Research on SNP variation is now a major focus of genomic studies aimed at improving meat quality. Leptin levels reflect the amount of adipose tissue in meat, also known as marbling. Several SNPs in the leptin gene and its receptor have been linked to this meat quality trait. Similarly, SNPs in the calpain/calpastatin system play a significant role in postmortem muscle proteolysis and pork tenderness. This review examines these genetic variants as markers involved in the expression of phenotypic traits in meat products and explores their mechanisms of action. Additionally, it provides insights into the genetic variants associated with production-related characteristics.