Stearoyl-CoA desaturase (SCD), including delta-9–18 desaturase [octadecenoic acid/octadecanoic acid], converts saturated fatty acids (SFAs) into monounsaturated fatty acids (MUFAs), which are linked to obesity, insulin resistance, and hypertension (21–23). This evidence concerns the gene SCD and obesity due to melanocortin 4 receptor deficiency.