Methylenetetrahydrofolate reductase (MTHFR) C677T and A1298C polymorphisms in breast cancer: a Sardinian preliminary case-control study

Two common polymorphisms in the MTHFR gene, C677T and A1298C, are associated with reduced
enzyme activity and may be associated with breast cancer susceptibility.
We performed a case-control study to investigate the association between the two SNPs in the MTHFR
gene and risk of breast cancer. In total, 58 breast cancer patients and 58 unaffected controls were
enrolled in the study. Polymerase chain reaction/restriction fragment length polymorphism technique
(PCR-RFLP) was conducted to determine the genotypes.
No significant differences were found in the genotypes of the two polymorphisms of the MTHFR gene
between cases and controls. The OR and 95% CI for the 677CC, 677CT and 677TT genotypes were 1.00,
0.95 (0.39-2.31) and 0.87 (0.27-2.80), respectively; those of the 1298AA, 1298AC and 1298CC genotypes
were 1.00, 0.59 (0.26-1.36) and 0.78 (1.32-4.66) respectively. Furthermore, it has been shown in patients
with breast cancer a risk of presenting with an aggressive biophenotype about twice or three times higher
in the presence of the C677T and A1298C polymorphisms, respectively. Finally, the
A1298Cpolymorphism is significantly associated with increased recurrence risk of lymph node-positive
breast cancer.
Our study has not shown a significant association between MTHFR gene polymorphisms and breast
cancer risk. However, it highlighted the key-role played by the presence of mutant alleles for both
polymorphisms in increasing the risk of developing more aggressive phenotypes; moreover, specifically in
A1298C, it might also lead to a higher risk of developing lymph node metastasis.