In metabolic disease conditions, increased circulatory levels of IL-8 and MCP-1 in obesity were found to be positively associated with body mass index (BMI), waist circumference, high-density lipoprotein (HDL) cholesterol, IL-6, c-reactive protein (CRP), and homeostatic model assessment of insulin resistance (HOMA-IR) [14]. The gene discussed is CCL2; the disease is obesity due to melanocortin 4 receptor deficiency.