Familial Mediterranean fever (FMF) is a major cause of AA amyloidosis. Recently, the gene (MEFV) causing this disease was cloned and 16 disease associated mutations have been described. We have analyzed 178 FMF patients, 30 of whom also suffered from amyloidosis, for 4 mutations in MEFV. Mutations were identified in 29 of the FMF amyloidosis patients. 27 FMF amyloidosis patients were homozygous for M694V. One patient was found to be homozygous for both V726A and E148Q. In another patient E148Q and V726A were found on one allele, while V726A was found on the second allele. Amyloidosis was far more common among patients homozygous for M694V compared to patients with other mutations (P < 0.0001). In 3 patients homozygous for M694V, amyloidosis was the sole manifestation of the disease.