MTHFR and rheumatoid arthritis: Saad et al. (12) showed that in an African American (Egyptian) population, the MTHFR 677C/T SNP was correlated with genetic susceptibility to RA under different genetic models (except the recessive model), and the 1298A/C gene SNP was correlated with genetic susceptibility to RA under dominant and codominant models, while Boughrara et al. (10) reported the opposite conclusions.