In chickens, PPARα mRNA expression was found to be negatively correlated with IMF from 0 to 8 w in thigh muscle tissue40. Carnitine palmitoyl transferase 2 (CPT2) is an enzyme required for mitochondrial long-chain fatty acid oxidation, and the loss of muscle CPT2led to accumulation of long-chain acylcarnitine and protected against diet-induced obesity and insulin resistance in mice41; Mitochondrial carnitine palmitoyl transferase 1a (CPT1A) in the liver mitochondrial outer membrane was found to catalyze the primary regulatory step in overall mitochondrial fatty acid oxidation42. This evidence concerns the gene CPT2 and obesity due to melanocortin 4 receptor deficiency.