Evaluation of the frequency of MEFV gene variants in patients with a pre-diagnosis of Familial Mediterranean Fever (FMF) in southeast Türkiye

Abstract

Purpose: Familial Mediterranean Fever (FMF) is a hereditary auto inflammatory disease (MIM#249100). The most common symptoms are abdominal pain, high fever, and arthralgia. FMF is the result of variants in the MEditerraneanFeVer (MEFV) gene located on chromosome 16p13.3, which contains 10 exons and encodes the pyrin (marenostrin) protein. The frequency of MEFV gene variants that cause FMF varies according to ethnic groups, countries and even different regions in the same country. In our study, we aimed to determine the frequency and distribution of MEFV gene changes that cause Familial Mediterranean fever in southeast Türkiye. Materials and methods: A total of 6.660 patients with a pre-diagnosis of FMF, including 3.495 women and 3.165 men, were included in the study. Fragment analysis was performed to investigate the MEFV gene variants of the patients and the 19 most common variants in the Turkish population were examined. Results: We found at least one variant in 50.17% (3.341) of our 6.660 patients. In our patients, 108 different genotypes; in Exon 2, 3, 5 and 10 and we identified 16 different variants. We found 2.120 (63.21%) patients were heterozygous, 693 (20.74%) were compound heterozygotes, 275 (8.23%) were homozygous and 261 (7.81%) were complex genotypes. The five variants with the highest allele frequency are; R202Q (27.84%), M694V (22.83%), E148Q (21.98%), V726A (7.42%), and M680I (G>C) (6.39%). Conclusion: We identified the most common prevalence of MEFV gene alteration in a large patient group in our region. High R202Q mutation rates were among the remarkable results of this study. © 2023, Pamukkale University. All rights reserved.