MTHFR and type 2 diabetes mellitus: In addition to these data on up- and down-interaction, we found that the following polymorphisms were in complete association with some members of the interaction networks (i.e., these polymorphism pairs are significantly interacting in the all three groups, NGT, IGM, T2DM): MTHFR(C677T), AGT(Met235Thr), LPL(Asp9Asn), F7(-323 10-bp Del/Ins), APOA4(Thr347Ser), APOC3(C-482T), APOC3(T-455C), APOC3(C3175), CETP(C-628A), CETP(Intron 1 TaqIB +/-) (see Table 5).