Background: This study is the first to investigate the association between colorectal cancer (CRC) risk and the hMLH1 −93G>A and hMSH2 1032G>A polymorphisms of mismatch repair (MMR) genes in the Azerbaijani population. Methods: Peripheral blood samples containing EDTA were collected from the study subjects (134 patients and 137 controls), and genomic DNA was extracted using the non-enzymatic salting-out method. Genotypes were determined by polymerase chain reaction–restriction fragment length polymorphism (PCR-RFLP), and the results were visualized through agarose gel electrophoresis. Results: Overall, no statistically significant correlation was observed between CRC risk and the hMLH1 −93G>A polymorphism in the heterozygous GA (OR = 0.760; 95% CI = 0.374–1.542; p = 0.446), the mutant AA (OR = 1.474; 95% CI = 0.738–2.945; p = 0.270), or the A allele (OR = 1.400; 95% CI = 0.984–1.995; p = 0.062). However, in contrast to the dominant model, a statistically significant association was found between the recessive model and an increased CRC risk, with an odds ratio of 1.788 (95% CI = 1.102–2.900; p = 0.018). The hMLH1 −93G>A polymorphism was identified at a significantly higher frequency across the TNM stages, with the distribution showing statistical significance (p < 0.05). Additionally, no statistically significant association was observed between the hMSH2 1032G>A polymorphism and CRC risk. Conclusions: Although no overall association was observed for hMLH1 −93G>A, our findings suggest a potential link with increased colorectal cancer risk under the recessive model in the Azerbaijani population. Further studies are warranted to confirm this model-specific association and investigate the underlying biological mechanisms.

Background: This study is the first to investigate the association between colorectal cancer (CRC) risk and the hMLH1 -93G>A and hMSH2 1032G>A polymorphisms of mismatch repair (MMR) genes in the Azerbaijani population. Methods: Peripheral blood samples containing EDTA were collected from the study subjects (134 patients and 137 controls), and genomic DNA was extracted using the non-enzymatic salting-out method. Genotypes were determined by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP), and the results were visualized through agarose gel electrophoresis. Results: Overall, no statistically significant correlation was observed between CRC risk and the hMLH1 -93G>A polymorphism in the heterozygous GA (OR=0.76; 95% CI=0.37–1.54; P=0.446), mutant AA (OR=1.47; 95% CI=0.74–2.95; P=0.270), or the A allele (OR=1.062; 95% CI=0.735–1.534; P=0.748). However, in contrast to the dominant model, a statistically significant association was found between the recessive model and a reduced CRC risk, with an odds ratio of 0.56 (95% CI=0.35–0.91; P=0.018). The hMLH1 -93G>A polymorphism was identified at a significantly higher frequency across the TNM stages, with the distribution showing statistical significance (P0.05). Additionally, no statistically significant association was observed between the hMSH2 1032G>A polymorphism and CRC risk. Conclusions: Our results indicate that the hMLH1 -93G>A polymorphism, particularly under the recessive model, may play a protective role against CRC risk in the Azerbajani population. Further studies are required to validate these results and investigate the underlying biological mechanisms.

Background/Objectives: Genetic polymorphisms in the BRCA2 gene have been implicated in breast cancer susceptibility. While numerous studies have investigated this polymorphism, its precise role in breast cancer development remains unclear. Furthermore, to the best of our knowledge, no related studies have been conducted in Azerbaijan. The aim of this study was to determine the distribution of the BRCA2 Met1915Thr polymorphism (rs4987117) in the Azerbaijani population and to evaluate its potential association with breast cancer risk. Methods: A total of 144 breast cancer patients and 152 healthy controls were recruited from the Oncology Clinic of Azerbaijan Medical University between 2021 and 2024. The Met1915Thr polymorphism was genotyped using PCR-RFLP and visualized on a 2% agarose gel. Results: A statistically significant association with increased breast cancer susceptibility was observed for the heterozygous Met/Thr genotype (OR = 1.83, 95%CI = 1.08–3.11, p = 0.02), the Thr allele (OR = 1.57, 95%CI = 1.12–2.20, p = 0.008), and under the dominant inheritance model (OR = 1.83, 95%CI = 1.15–2.90, p = 0.01). Notably, this association was more evident among individuals aged over 58 years, in whom the Met/Thr genotype conferred a significantly elevated risk (OR = 2.35, 95%CI = 1.17–4.73, p = 0.02). Conclusions: The BRCA2 Met1915Thr polymorphism is associated with an increased risk of breast cancer in the Azerbaijani population. These findings suggest a potential role of this polymorphism in breast cancer susceptibility and highlight the need for further studies in larger cohorts to validate these associations.

Background: Breast cancer (BC) is the most common malignancy among women, and genetic predisposition plays a critical role in its development. Among DNA mismatch repair (MMR) genes, MLH1 is essential for maintaining genomic stability, and promoter variants may influence its transcriptional regulation. Variants in MMR genes, including MLH1, have been implicated in cancer susceptibility; however, evidence regarding the promoter polymorphism −93G>A (rs1800734) and its association with BC remains limited and inconsistent across populations. Methods: We conducted a case–control study of 143 breast cancer patients and 161 cancer-free controls of Azerbaijani origin. Genotyping of MLH1 −93G>A was performed using PCR-RFLP and validated by next-generation sequencing (NGS). Odds ratios (ORs) and 95% confidence intervals (CIs) were calculated under different genetic models by logistic regression, followed by false discovery rate (FDR) correction for multiple testing. Results: The genotype distribution among patients was 25.9% GG, 58.7% GA, and 15.4% AA, compared with 37.9%, 46.6%, and 15.5% in controls. A significant association was observed between the GA genotype and BC risk (OR = 1.855, 95% CI: 1.104–3.085, p = 0.019). In the dominant model (GA + AA vs. GG), carriers of the A allele showed increased breast cancer risk (OR = 1.747, 95% CI: 1.069–2.856, p = 0.026). Genotype distribution was also associated with tumor grade (p = 0.047) and stage (p = 0.013). However, none of the associations remained significant after FDR adjustment. Conclusions: This pilot study provides the first evidence from Azerbaijan suggesting a potential role of the MLH1 −93G>A variant in breast cancer susceptibility. Although the associations were nominal and require validation in larger cohorts, the findings point to a biologically plausible link between MLH1 promoter variation and impaired MMR activity, which may contribute to polygenic breast cancer risk. These preliminary results emphasize the importance of evaluating MMR gene variants in underrepresented populations and support further studies integrating functional assays and broader gene coverage.