Cluster of patients with Familial Mediterranean fever and heterozygous carriers of mutations in MEFV gene in the Czech Republic.

Familial Mediterranean fever (FMF) is a well-described monogenic autosomal recessive disorder with highest occurrence in the Mediterranean region. In this article, we describe the experience of a center in the Czech Republic that follows four families with members bearing mutations in MEFV gene without provable ancestry from the Mediterranean region. We also discuss the clinical picture of the heterozygous variants that were present in our cohort. The typical clinical presentation in heterozygotes corresponds to data described in the international literature. The possibility of combination of mutations and/or polymorphisms in different genes and epigenetic or environmental influences on the clinical symptoms are taken into account.