Moreover, we found a relation between the methylation level of the MEFV exon 2 and the phenotype, as demonstrated by FMF patients complaining of abdominal pain, arthritis, erysipeloid erythema, and constipation/diarrhea who had non-significant higher methylation% than those with fever and chest pain, while another study highlighted that there is no relation between the methylation% of exon 2 in the MEFV gene and clinical symptoms [10]. This evidence concerns the gene MEFV and arthritic joint disease.