For example, in 97 patients with obesity underwent either RYGB or biliopancreatic diversion with duodenal switch, decreased levels of IFN-γ, hs-CRP, TNF-α, IL-13, IL-6, IL-1ra, C3, and leptin were described compared with baseline levels at 1-year follow-up55. The gene discussed is TNF; the disease is obesity due to melanocortin 4 receptor deficiency.