FABP4 and obesity due to melanocortin 4 receptor deficiency: FABP4 has also been introduced as a fat-derived circulating protein and a potent clinical biomarker for metabolic and cardiovascular diseases such as obesity, type 2 diabetes, hypertension, dyslipidemia, atherosclerosis, non-alcoholic fatty liver disease, ischemic heart disease, heart failure and renal failure in various cross-sectional and interventional studies3,4.