IRF5 and obesity due to melanocortin 4 receptor deficiency: In the past 5 years, IRF5 has become a molecule of high interest given its important role(s) in regulating inflammation and immunity7, 8, 10, 19, 22, 24, as well as recent new findings that implicate IRF5 in the regulation of neuropathic pain, obesity, myocardial infarction, allograft rejection, atherosclerosis, and metabolic dysfunction25, 26, 27, 28, 42.