Protein expression of colonic RGS9 was additionally confirmed to be overexpressed in obesity (n = 10), compared to lean (n = 9) (1.23 ± 0.28 vs. 0.99 ± 0.11, respectively, mean difference 0.24 [95% CI 0.035–0.45], Log2FC = 0.30, p = 0.026) (Supplemental Figure S3). This evidence concerns the gene RGS9 and obesity due to melanocortin 4 receptor deficiency.