Mice deficient in osteopontin have improved glucose tolerance and lower fasting plasma glucose, insulin, triglycerides, and proinflammatory cytokines after high fat diet regime compared to wild-type mice (129) and antibody-mediated neutralization of osteopontin action reduces obesity-induced inflammation and insulin resistance (207). The gene discussed is INS; the disease is obesity due to melanocortin 4 receptor deficiency.