The R172 locus mutation can influence IDH2-encoded protein isocitrate dehydrogenase activity by decreasing the levels of intracellular α-ketoglutarate, which may promote the conversion of isocitrate to 2-hydroxyglutarate (2-HG); The resultant overaccumulation of 2-HG causes excessive cellular proliferation, which, in turn, contributes to oncogenic changes and tumor growth and promotes tumor development (2). This evidence concerns the gene IDH2 and neoplasm.