Comprehensive Genetic Map of Muscle Lipidome Reveals Novel Insights Into Flavor Variation in Ruminant Meat

Abstract

Ruminant meat is an important component of human diets, valued for its unique flavor and nutritional density. Lipids play a dominant role in shaping meat flavor, yet their genetic and biochemical basis remains unexplored. Here, from the analysis of 434 sheep longissimus thoracis samples, the current study presents the first comprehensive lipid map of sheep meat, including 947 lipids. A substantial proportion of these lipids exhibit moderate-to-high heritability, with 51.6% surpassing a heritability of 0.2 and 15.8% exceeding 0.45. Metabolome-based genome-wide association analysis identifies 467 significant loci affecting 233 lipids, including 110 loci exhibiting pleiotropy. Notably, the levels of monogalactosyldiacylglycerols containing oleic (C18:1) and linoleic (C18:2) acids are specifically regulated by the expression of MBOAT1 and PAQR8 genes, respectively, while 13 triglycerides and one diglyceride are co-regulated by SH2D4A. The levels of phosphatidylethanolamine PE(20:4_20:0) are regulated by VPS53. Further examination of volatile compounds demonstrates that variations in these genetically controlled lipids significantly impact flavourant levels in cooked meat. Given the conservation of lipid profiles and genomes among ruminants, this study offers novel insights into the genetic architecture underlying meat lipid metabolism and provides a valuable resource for the targeted genetic improvement of ruminant meat flavor.