breast diseases, history of breast cancer in the first-degree family, early menstruation, late menopause, nulliparity, and higher socioeconomic status (Kamińska et al., 2015). Genetic factors also play an important role in tumor formation and progression. For example, aneusomy of chromosome 17, deletion of loci at 16q, 11q, 6q, and 3p and polymorphisms in genes involved in the key cellular pathways can be the main risk factors for breast cancer (Newsham, 1998). One of the important cellular pathways is the folate metabolism cycle which includes many genes such as methylenetetrahydrofolate reductase (MTHFR), methionine synthase (MTR), and methionine synthase reductase (MTRR). The role of the MTHFR enzyme is to convert 5,10-methylenetetrahydrofolate (5,10-MTHF) to