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

Abstract

Purpose: Familial Mediterranean Fever (FMF) is a hereditary auto inflammatory disease (MIM#249100). The most common symptoms are high fever, abdominal pain and arthralgia. FMF is the result of variations in the MEditerraneanFeVer (MEFV) gene, which is located on chromosome 16p13.3, consists of 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 this study, we aimed to determine the frequency and distribution of MEFV gene alterations that cause Familial Mediterranean fever in southeastern Turkey. Materials and Methods: A total of 6,660 patients with a prediagnosis of FMF, including 3,495 women and 3,165 men, were included in the study. Fragment analysis was performed to investigate the MEFV gene variations of the patients and the 19 most common variants in the Turkish population were examined. Results: We found at least one variation 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 variations. We found 2,120 (63.21%) patients heterozygous, 693 (20.74%) compound heterozygotes, 275 (8.23%) homozygous and 261 (7.81%) complex genotypes. The 5 variants with the highest allele frequency are respectively; 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.