TNFRSF1B and Insulin resistance: Indeed, the top KEGG category in our analysis is 'Cytokine-cytokine receptor interaction', and includes the genes Ccl2 and Tnfrsf1b. The Ccl2 gene encodes a C-X-C family cytokine that is a ligand for the receptor Ccr2, a key mediator of diet-induced obesity and insulin resistance [14].