PPARA and obesity due to melanocortin 4 receptor deficiency: However, a limitation of the study was not having carried out an assessment of the expression of obesity-related genes such as family peroxisome proliferator-activated receptor (PPAR), adipocyte fatty acid binding protein (AFABP, also known as aP2 and FABP4), and stearoyl-CoA desaturase (SCD).