Similarly, the MTHFR 1298 A>C assessment did not disclose significant differences in the genotypic and allelic frequencies between patients and controls (RA patients: AA, 48.6%; AC, 41.2%; CC, 10.2%; C-allele frequency, 30.8%; and controls: AA, 49.7%; AC, 40.2%; CC 10.1%; C-allele frequency, 30.2%). This evidence concerns the gene MTHFR and rheumatoid arthritis.