FMF Genotype-phenotype correlation in Iranian Azeri Turks: Association between M694V/R761H mutation and amyloidosis

Familial Mediterranean fever (FMF), an inherited autosomal recessive disorder, is frequently present among individuals of Mediterranean origin. Differences in the clinical manifestations of FMF between different ethnic groups have been documented. The aim of the present study was to determine the most common characteristics of FMF and the relationship between clinical findings and the most common mutant alleles of the MEFV gene in an Iranian Azeri Turk population. We analyzed clinical and genetic data from 415 patients identified as having FMF clinical symptoms and who were referred to the Molecular Genetics Laboratory of Tabriz/Iran over the last 3 years. The mutation type and clinical characteristics were determined for each patient. The following primary clinical characteristics of the patients were observed: peritonitis was observed in 378 (93.8%), high-grade fever in 351 (86.88%), arthritis in 215 (54.57%), pleuritis in 207 (53.49%), myalgia in 153 (41.69%), AA amyloidosis in 149 (40.16%), and erysipelas-like erythema in 54 (14.96%) subjects. A positive response to colchicines treatment was noted in 374 (95.1%) patients including 303 patients with two mutated alleles and 71 patients with one identified mutation. In contrast to previous studies, there was no significant association between M694V mutation and development of amyloidosis. The M680I/M680I, M680I, M694I, and M694V/R761H genotypes were found to be associated with the development of amyloidosis. These results indicate that physicians need to pay careful attention to patients with asymptomatic or mildly symptomatic FMF with these genotypes.