As with colon cancer, relations between pancreatic cancer and BMI have been attributed to the growth-promoting effects of elevated insulin and IGFs secondary to obesity (Takeda and Escribano, 1991), although the carcinogenic effects of insulin have also been proposed to explain positive associations with abnormal glucose metabolism (Gapstur et al, 2000) or diabetes mellitus (Everhart and Wright, 1995). The gene discussed is INS; the disease is obesity due to melanocortin 4 receptor deficiency.