PECR is located within broad linkage peaks for several alcohol-related traits, including alcoholism (67), comorbid alcoholism and depression (68), level of response to alcohol (69) and amplitude of the P300 response (a neuronal feature related to decision-making) (70, 71). Expression of PECR is highest in the liver, followed by the kidney, muscle tissue, the lungs, and the heart but barely, if at all, in the human brain (71), although it was expressed in rodent brain in the present study. If this gene is involved in alcohol dependence, it must act in the periphery more possibly than in the central nervous system. PECR is a member of the short-chain dehydrogenase family of enzymes. It is a key enzyme of fatty acid metabolism. It catalyzes the reduction of medium-chain (unsaturated) enoyl-CoAs to saturated acyl-CoAs, which may then undergo oxidation in mitochondria for energy production. This pathway is particularly important in conditions of starvation, when the energy supply is switched from the use of glucose to fatty acids. This pathway originates from triglycerides that are typically increased in the blood of alcohol-dependent individuals
