SCD and obesity due to melanocortin 4 receptor deficiency: Stearoyl‐CoA desaturase 1 (SCD‐1) is the rate‐limiting enzyme in the biosynthesis of monounsaturated fatty acids, and we extracted liver tissue to analyse the levels of FAIM and PACAP in the obesity group (n = 5) and control group (n = 5); obese mice had significantly lower levels of FAIM and PACAP, while they had significantly higher levels of SCD1 (Figure S6F).