We aimed to investigate the effect of gene polymorphisms involved in the inflammatory pathway [IL6 (interleukin 6), IL6R (interleukin 6 receptor), FOXP3 (forkhead box P3), TLR2 (toll-like receptor 2), TLR4 (toll-like receptor 4), IFNL3 (interferon lambda 3, formerly known as IL28B), and IFNL4 (interferon lambda 4, formerly known as IL29)] on lipid metabolism in Chinese individuals with obesity. The gene discussed is IFNL4; the disease is obesity due to melanocortin 4 receptor deficiency.