Accumulation of excessive amounts of storage lipids into adipose tissue causes adipocyte hypertrophy with the development of obesity, subsequently resulting in secretion abnormalities of FFA and adipocytokines such as TNF-alpha, IL-6 and adiponectin derived from adipocytes, which are involved in insulin resistance [1]. The gene discussed is TNF; the disease is obesity due to melanocortin 4 receptor deficiency.