No correlation between MTHFR c.677 C > T, MTHFR c.1298 A > C, and ABCB1 c.3435 C > T polymorphisms and methotrexate therapeutic outcome of rheumatoid arthritis in West Algerian population

Context The c.677 C > T and c.1298 A > C polymorphisms of methylenetatrahydrofolate reductase ( MTHFR ) gene and c.3435 C > T polymorphism of ATP-Binding cassette B1 ( ABCB1 ) gene are reported as pharmacogenetic markers, influencing the methotrexate (MTX) therapeutic outcome in rheumatoid arthritis (RA) patients. Objectives The aims of this study were to determine the relationship between these polymorphisms and clinical response and/or adverse drug reaction (ADRs) to MTX treatment. Materials and methods The cohort of our study was composed of 110 RA patients of the West Algerian population. The clinical response was evaluated using the disease activity score 28 (DAS28) and the ADRs were collected after physical examination of patients. All samples were genotyped for theses polymorphisms by TaqMan ® allelic discrimination assay. Results Based on EULAR criteria, 59.09% RA patients were responders and ADRs were observed in 40.9% patients. The frequency distribution of these three polymorphisms was similar between the responders and the non-responders. The same result was found on ADRs study and no significant difference of distribution between the presence of ADRs group and absence of ADRs group was observed. Discussion Our study joins the results that found in others population in the world. Conclusion We have demonstrated, for the first time in the West Algerian population, that these polymorphisms were not predictive for clinical response and/or ADRs to MTX therapeutic outcome.