The silencing of glutaminase through promoter hypermethylation has been confirmed in colon cancer (67), and if such an effect occurs in response to dietary methyl-donors (e.g., Met, choline, and vitamin B12) it may alter the ability of this enzyme, which is abundant in gut intestinal cells, to utilize glutamine to generate glutamate (68). The gene discussed is GLS; the disease is malignant colon neoplasm.