RESUMEN
Background:TNF-α has a dual role in multiple sclerosis (MS), contributing to both protective and harmful effects. It activates immune cells, promotes the formation of inflammatory lesions in the central nervous system, and stimulates the production of other pro-inflammatory cytokines and chemokines, leading to myelin destruction and neuronal damage. Our research focused on investigating the relationship between TNF-alpha (rs1800630, rs1800629, and rs361525) gene polymorphisms and MS. Methods: 250 healthy controls and 250 multiple sclerosis (MS) patients were included in the study. DNA was extracted from leucocytes from peripheral venous blood by salt precipitation. Single nucleotide polymorphisms (SNPs) were tested using RT-PCR. Statistical analysis of the data was performed using IBM SPSS Statistics 29.0 data analysis software. Results: The analysis revealed that the rs361525 AG genotype was significantly less frequent in the MS group compared to the control group (4.0% vs. 7.2%, p = 0.042). Sex-specific analysis showed a significant difference in genotype distribution (GG, AG, AA) among males between the MS group and the control group (97.7%, 0%, 2.3% vs. 90.6%, 9.4%, 0%, p = 0.005). For the rs1800629 polymorphism, significant results were also found. In subjects younger than 39 years, the A allele was significantly less frequent in the MS group than in the control group (8.6% vs. 15.0%, p = 0.030). The most robust model indicated that the AA genotype reduced the odds of MS by approximately 2 fold compared to the AG + GG genotype (p = 0.044), and each A allele reduced the odds of MS by approximately 2 fold (p = 0.028). The rs1800630 A allele was significantly more common in males in the MS group than in the control group (21.0% vs. 12.9%, p = 0.046). Conclusions: In conclusion, our study identifies significant associations between TNF-alpha gene variants and MS. Specifically, the rs631525 AG genotype was less common in the MS group, with notable sex-specific differences observed. The rs1800629 A allele was statistically significantly less frequent in the MS group than in the control group, and the AA genotype reduced the odds of MS occurrence by ~2 fold compared with the AG + GG genotypes. Additionally, each A allele of rs1800629 was linked to a 2-fold decreased odds of MS occurrence. In males, the rs1800630 A allele was more frequent in the MS group. These findings highlight the relevance of TNF-alpha genetic variations in MS susceptibility, suggesting potential avenues for further research and therapeutic exploration.