Abstract

MicroRNA (miRNA) polymorphisms can influence gene regulation and cancer susceptibility. A previous bioinformatics study suggested that the single nucleotide polymorphism rs1514422, located in the mature sequence of hsa-miR-8060, could alter miRNA-mRNA interactions, potentially influencing oncogenic regulation in breast cancer (BC). However, rs1514422 has not previously been the subject of experimental studies. This case–control study analyzed 100 DNA samples (50 BC cases, 50 controls) from Vietnamese women. Rs1514422 was genotyped as part of a panel of 101 SNPs in 100 mature miRNA coding genes. Statistical analyses, including chi-squared tests and logistic regression analyses, were conducted to evaluate genotype–phenotype associations. The results indicate that the GG genotype was significantly more frequent in BC cases (70%) than in controls (40%), while the GA genotype was more common in controls (56%) than in cases (26%). The A allele was associated with reduced BC risk (odds ratio (OR) = 0.38; p = 0.0081), while the GA genotype exhibited a protective effect in dominant (OR = 0.29; p = 0.0024) and overdominant models (OR = 0.28; p = 0.0021). These findings align with previous computational predictions, suggesting that the A allele may enhance the miRNA-mediated suppression of KRAS, thus reducing oncogenic activity. This study provides the first experimental evidence linking rs1514422 to breast cancer susceptibility, with Vietnam as the first population studied. The A allele and GA genotype appear to confer protective benefits, supporting prior bioinformatics predictions. Further research is needed to confirm its functional impact on KRAS regulation.