MEFV mutations in Egyptian patients suffering from familial Mediterranean fever: analysis of 12 gene mutations.

The objective of the study is to screen 12 MEFV gene mutations in Egyptian patients with familial Mediterranean fever (FMF) and to study the initial hypothesis that the phenotypic expression of the disease may be attributable to the existence of a particular mutation. We enrolled 136 Egyptian patients (74 males, and 62 females) with a clinical diagnosis of FMF. DNA was amplified by PCR and subjected to reverse hybridization for the detection of 12 MEFV gene mutations. The phenotypic expression of the disease was compared in two subgroups according to the presence of homozygote E148Q and M694V gene mutations. The most frequent gene mutations in the studied group were V726A, M694V, M680I, E148Q and M694I in 41.2, 32.4, 29.4, 25 and 20.6%, respectively. At least one of these main five founder mutations was present in 132 patients (97.1%). Thirty-two patients (23.5%) were homozygote for one of the main five founder mutations. The most common homozygote gene mutations were E148Q and M694V, each in 12 patients (8.8%). Significant increase in abdominal pain and arthritis was found in patients with homozygote M694V mutation compared to those with E148Q mutation. All patients with amyloidosis had M694V gene mutation. The increased frequency of V726A gene mutation and the rarity of amyloidosis in this study suggest that Egyptian patients may have a milder form of FMF compared to other populations. The five main founder mutations account for the vast majority of cases of FMF. M694V gene mutation may be associated with increased frequency of abdominal pain, arthritis and the presence of amyloidosis.