Genetic Determinants of Fatty Acid Composition in Subcutaneous and Visceral Adipose Tissue.

Abstract

Fatty acids in adipose tissue are key structural and metabolic regulators of cardiometabolic health, but the genetic architecture governing depot-specific composition in subcutaneous (SAT) and visceral adipose tissue (VAT) is not well defined. We used MRI-derived estimates of fatty acid composition in SAT and VAT from 33,583 UK Biobank participants to perform genome-wide association studies. Functional annotation, fine mapping, colocalization, and expression QTL analyses were conducted to prioritize likely causal variants and explore mechanisms. We identified six loci associated with adipose tissue fatty acid composition, including both shared (PKD2L1, INSIG1) and depot-specific associations (LEKR1 and KLF14 for SAT; CDCA2 for VAT). The strongest association, rs603424-G (near PKD2L1), was linked to higher monounsaturated and polyunsaturated fatty acids, lower saturated fatty acids, and increased SCD1 expression in SAT and VAT, suggesting a role in desaturation and lipid remodeling. Several loci were linked to cardiometabolic outcomes including type 2 diabetes, hypertension, and cholelithiasis, with functional evidence supporting gene-diet interactions at the PKD2L1 locus. Our findings uncover genetic determinants of human adipose tissue fatty acid composition, highlight depot-specific regulation, and point to SCD1 as a potential metabolic regulator. These results deepen understanding of lipid metabolism and its links to cardiometabolic risk.