Unraveling the genetic underpinnings of fat metabolism and SDR16C5 mediated molecular mechanisms in adipogenesis of domestic pigs

Fat metabolism plays a pivotal role in determining meat quality and economic value in domestic pigs, yet its underlying genetic mechanisms remain poorly understood. To clarify the molecular basis of adipose deposition, this study integrated whole-genome resequencing data from 226 individuals across 61 Eurasian pig breeds and applied population genetic and selective sweep analyses to identify and validate candidate genes involved in fat metabolism. Significant genetic divergence was observed between Asian and European domestic pigs, with higher linkage disequilibrium (LD) levels in domestic breeds likely driven by artificial selection during domestication. High-fat groups (backfat thickness: 39 mm; fat percentage: 35%) exhibited substantially greater fat deposition than low-fat groups (backfat thickness: 15 mm; fat percentage: 15%). Combined analyses of Pi-ratio, XP-EHH, and F ST revealed 13 key candidate genes, including SDR16C5 and CPE , functionally enriched for lipid metabolism pathways such as fatty acid metabolism and insulin signaling. Cellular assays further confirmed that SDR16C5 promotes adipogenesis by enhancing preadipocyte proliferation and lipid accumulation. This study identifies SDR16C5 as a candidate regulator of adipogenesis and fat metabolism in pigs. These findings establish a genetic framework that may facilitate targeted breeding strategies to improve fat composition and enhance premium pork production.