Considering the key role of the innate immune system in obesity-induced inflammation, the regulatory function of CCR2 on inflammation and the recruitment of macrophages to insulin-sensitive tissues in response to HFD-induced obesity, we investigated the role of CCR2 in abnormal glucose disorder and inflammation of adipose tissue induced by HFD. The gene discussed is INS; the disease is obesity due to melanocortin 4 receptor deficiency.