FASN, SCD, and PLAG1 Gene Polymorphism and Association with Carcass Traits and Fatty Acid Profile in Hanwoo Cattle

Genetic polymorphisms have a great impact on enhancing quantitative traits in cattle. In this study, Fatty acid synthase (<i>FASN</i>) g. 16024 (A>G), Stearoyl-CoA desaturase (<i>SCD</i>) g. 10329 (C>T), and pleomorphic adenoma gene (<i>PLAG1</i>) g. 25003338 (C>G) genotypic and allelic polymorphisms were evaluated, along with their associations with fatty acid composition, adipogenic gene expression, and carcass characteristics (carcass weight, yield grade, backfat thickness, and marbling score) in Hanwoo steers. A total of 128 Hanwoo steers were selected for this study and the Polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method was used to identify polymorphism of these genes. The AG genotype and G allele in <i>FASN</i> g. 16024 (A>G), CT genotype and T allele in <i>SCD</i> g. 10329 (C>T), and GG genotype and G allele in <i>PLAG1</i> g. 25003338 (C>G) showed higher frequency and positively correlated with carcass traits, yield, and quality grades. Fatty acid composition results indicate that C18:3n-6, C20:1, and C20:2n-6 were significantly higher in the AA genotype of <i>FASN</i> gene, C14:1 and C18:3n-6 in the CC genotype, and C16:1 in the TT genotype of <i>SCD</i> gene. C12:0, C14:0, C16:1, C18:0, and C20:0 were higher in the CC genotype of <i>PLAG1</i> gene. Furthermore, RT-qPCR analysis of adipogenesis-related genes (AMP-activated protein kinase-α (<i>AMPKα</i>), Carnitine palmitoyl transferase-1β (<i>CPT1</i>), G-coupled protein receptor-43 (<i>GPR43</i>), and <i>SCD</i>) across different SNP genotypes suggests a systemic interaction between genetic factors and adipogenesis in beef cattle. This study emphasizes the significance of <i>FASN</i> g. 16024 (A>G), <i>SCD</i> g. 10329 (C>T), and <i>PLAG1</i> g. 25003338 (C>G) SNPs for genetic selection to enhance beef quality and elucidate lipid metabolic pathways in Hanwoo cattle.