FAS and obesity due to melanocortin 4 receptor deficiency: CAP’s pattern of gene expression is more similar to that of LC1 with decreases in mRNAs for the lipogenic genes FAS and SCD; SCD is a key regulatory enzyme in triglyceride production, and a decrease in its activity is associated with a variety of beneficial endpoints including attenuation of weight gain and obesity (Jeffcoat, 2007).