Microarray analysis of circulating microRNAs in familial Mediterranean fever

<p><b>Objectives:</b> Familial Mediterranean fever (FMF) is an autoinflammatory disease caused by mutations in <i>MEFV</i>. Mutations in exon 10 are associated with typical FMF phenotypes, whereas the pathogenic role of variants in exons 2 and 3 remains uncertain. Recent evidence suggests that circulating microRNAs (miRNAs) are potentially useful biomarkers in several diseases. Therefore, their expression was assessed in FMF.</p> <p><b>Methods:</b> The subjects were 24 patients with FMF who were between attacks: eight with exon 10 mutations (group A), eight with exon 3 mutations (group B), and eight without exon 3 or 10 mutations (group C). We also investigated eight cases of PFAPA as disease controls. Exosome-rich fractionated RNA was subjected to miRNA profiling by microarray.</p> <p><b>Results:</b> Using the expression patterns of 26 miRNAs, we classified FMF (groups A, B, and C) and PFAPA with 78.1% accuracy. In FMF patients, groups A and B, A and C, and B and C were distinguished with 93.8, 87.5, and 100% accuracy using 24, 30, and 25 miRNA expression patterns, respectively.</p> <p><b>Conclusions:</b> These findings suggest that expression patterns of circulating miRNAs differ among FMF subgroups based on <i>MEFV</i> mutations between FMF episodes. These patterns may serve as a useful biomarker for detecting subgroups of FMF.</p>