MEFV and rheumatoid arthritis: On the other hand, another study in Turkey also reported the high presence of MEFV mutations (E148Q, M694V, M694I, M680I, V726A, A744S, R761H, and P369S) and that the carrier rates of these MEFV mutations were 25.2% in RA and 23.3% in CG and suggest that mutations in the MEFV gene appear to be an aggravating factor in the severity of RA [17].