Although epidemiological studies had linked inflammation with obesity for decades, the underlying mechanisms remained obscured until the last decade when strong evidence indicated that obesity is a condition associated with chronic inflammatory activity due to incessant activation of a wide variety of inflammatory mediators including NF-κB, TNF-α and JNK [25–35]. The gene discussed is NFKB1; the disease is obesity due to melanocortin 4 receptor deficiency.