MTHFR and breast cancer: The results demonstrated that both polymorphisms are correlated with BC and it can be seen that there is a tendency towards the association between aggressiveness of tumor type and (ER-/PR-), over expression of HER2 neu, tumor size and stage with the mutant allele variants of MTHFR rs1801133 TT and MTHFR rs1801131 CC giving very highly significant values.