Nonetheless, contradicting the implied protective role [23], animal studies have implicated IL-13 in the development of metaplasia during gastric carcinogenesis (reviewed in [22]) and obesity-related CRC [18] while our own results have shown systemic interleukin to be elevated in both CRC [39] and high-risk conditions [46]. The gene discussed is IL13; the disease is obesity due to melanocortin 4 receptor deficiency.