The impact of MTHFR polymorphisms was addressed in a meta-analysis by Cen et al., who concluded that the MTHFR 677C>T polymorphism increases genetic susceptibility to RA in Asians, while the MTHFR 1298A>C polymorphism increases susceptibility in the general population [175]. The gene discussed is MTHFR; the disease is rheumatoid arthritis.