Spectrum of Mutations of Familial Mediterranean Fever Gene by Whole Sequencing Method in Iranian Patients

Background: Familial Mediterranean fever (FMF) is the most common type of periodic fever syndrome. The disease is most prevalent in the western Mediterranean population, but today it is widespread in the world due to the large ethnic migrations of Turks, Jews, Arabs and Armenians. The MEFV gene is the only gene known to be associated with the disease. Objectives: The aim of this study was to characterize pathogenic mutations in patients with typical FMF symptoms by sequencing the entire MEFV gene. Methods: This is a descriptive-analytical study that was performed during ten years from 2009 to 2019. On 252 patients after clinical diagnosis based on existing criteria to determine mutations referred to Tehran Medical Genetics Laboratory and the whole sequencing method for MEFV gene was used to determine mutations. Results: Out of 252 patients, 143 (56.7%) had pathogenic variants, and 109 (43.3%) had no variants reported as pathogenic mutations. Variants were identified as fallow: (1) 8.7% as homozygous; (2) 22.2% as compound heterozygous; (3) 25.7% as heterozygous. The most common variants were M694V (c.2080A > G) and E148Q (c.442G > C). Conclusions: This study showed that the age of onset of the disease was in the first and second decades of life amongst our patients and the most common complaints of patients were periodic fever and abdominal pain. The most frequent allele was M694V (c.2080A > G) followed by E148Q (c.442G > C) allele.