Pnpla2 (adipose triglyceride lipase (ATGL)) initiates the first step of triglyceride hydrolysis and is a rate-limiting regulator of lipolysis; its deficiency results in lipid accumulation in hearts, obesity, cardiometabolic dysfunction, and impaired thermogenesis [78, 79]. Here, PNPLA2 is linked to obesity due to melanocortin 4 receptor deficiency.