Clinical Evaluation of a Reverse Hybridization Assay for the Molecular Detection of Twelve MEFV Gene Mutations

Abstract

Familial Mediterranean fever (FMF) is an autosomal-recessive disorder (MIM 249100) characterized by recurrent attacks of fever and serositis, affecting principally Sephardic Jewish, Armenian, Arab, and Turkish populations. Early diagnosis is important to initiate colchicine therapy, which prevents the occurrence of attacks and of renal amyloidosis, the major complication of the disease. The identification of MEFV (1)(2), the gene responsible for the disease, allowed the use of an early molecular test of diagnostic value for FMF patients (3), which negates the needs for unnecessary invasive investigations. The MEFV gene, located on chromosome 16p13.3, contains 10 exons and encodes the marenostrin/pyrin protein, a molecule acting as a regulator of the proinflammatory interleukin-1-dependent pathway and of the apoptosis mediated by the apoptosis-associated Speck-like protein containing a CARD (ASC) (4)(5), and which belongs to the death domain-fold family (6). More than 40 different FMF-associated mutations have been described to date (7), the most frequent ones being located in exon 10. Indeed, the M694V, V726A, M680I, and M694I mutations account for 65–95% of FMF alleles depending on the ethnic origin of the patient (8). E148Q is a frequent sequence variation situated in exon 2, but its involvement in the development of the disease remains controversial (9). The molecular diagnosis of FMF is based on various methods, including tedious and time-consuming scanning techniques such as denaturing gradient gel electrophoresis (DGGE) (3) or direct sequencing (10). Restriction enzyme analysis enables the detection of known mutations but still requires multiple DNA amplifications. An in-house amplification refractory mutation system has been designed, but it detects only three mutations (11). Because the spectrum of the most frequent mutations in FMF has been characterized in all at-risk populations, a new method aimed at identifying a set of selected common mutations in a single step would be …