Association Between Genetic Variant in the pre-miR-27a Oncogene and Risk of Breast Cancer and Metastasis

Background and Single-nucleotide polymorphisms (SNPs) within miRNA genes may be related with risk of cancer. A main SNP in the pre-miR-27a (rs895819) with an A to G variation was earlier identified. In this study, we aimed to explore any association between SNP rs895819 in the miR-27a gene and breast cancer susceptibility.
This case-control study included 120 breast cancer patients and 120 health controls. Genotyping was done by PCR-RFLP method and then verified using direct sequencing. Allele and genotype frequencies for SNP were examined by statistical analysis.
Compared with AA homozygote, samples carrying AG/GG genotypes had a statistically significant reduced predisposition to breast cancer (OR = 0.504, 95% CI = 0.3- 0.846). Frequency of G alleles for rs895819 variation was 20.8% in patients and 30% in controls, indicating a reduced sporadic breast cancer risk ([G] vs. [A]: OR = 0.614, 95% CI 0.405–0.931, P =0.021). Moreover, age investigation showed that the protective influence was mostly detected in women aged ≥45 years ([AG] vs. [AA]: OR = 0.205, 95% CI 0.093–0.452, P = 0.001).
Our study demonstrated that rs895819 in hsa-miR-27a is associated with reduced risk of breast cancer, particularly in younger individuals. Therefore, it might be potentially a useful genetic biomarker for breast cancer screening.