Is Turkish MEFV Mutations Spectrum Different Among Regions?

Abstract

Familial Mediterranean fever (FMF) is an autosomal recessive inherited inflammatory disease. The gene responsible for the disease, called MEFV, encodes a protein called pyrin or marenostrin. According to recent data, MEFV mutations are not the only cause of FMF, but genetic analysis of MEFV gene is needed for confirming the diagnosis of FMF. In the present study, we aimed to evaluate the molecular testing results of MEFV mutations. Molecular testing results of 1,435 patients were retrospectively evaluated over the last 4 years. These patients were identified as having FMF clinical symptoms. Patients were tested for 12 common mutations in the MEFV gene using a strip assay technique. From all 1,435 patients, MEFV mutations were found in 776 patients (54.08%) and 659 patients (45.92%) did not carry any mutations. Patients with mutations were classified as homozygotes (n = 148), compound heterozygotes (n = 197), heterozygous (n = 427), and complex genotypes (n = 4, patients with three mutations). Allelic frequencies for the four most common mutations in the mutation-positive groups were 48.79% (M694V), 14.86% (M680I G/C), 13.70% (E148Q), and 12.35% (V726A). The remaining alleles (10.3%) showed rare mutations that were R761H, P369S, A744S, K695R, F479L, and M694I. No patient showed a I692del mutation that is sometimes evident in other Mediterranean populations. It was found that the most common four mutations (M694V, M680I [G/C], E148Q, V726A) were similar to those previously reported from different regions of Turkey and this study might add some knowledge to the mutational spectrum data on FMF.