TNF and diabetes mellitus: Comparing frequencies of TNF-308G→A and other TNF promoter variants in p.C282Y homozygotes with and without diabetes would provide insights into the role of tumor necrosis factor in hemochromatosis-associated diabetes. PCSK7 rs236918 genotyping in p.C282Y homozygotes may reveal relationships of cirrhosis risk [165] and changes in insulin sensitivity with dietary carbohydrate intake [166].