Identification of novel serum microRNAs in age-related macular degeneration

Purpose: To identify circulating microRNAs (miRNA) associated with age-related macular degeneration (AMD). Thus differentially expressed serum miRNA could be used as AMD biomarkers. Methods: This study involved total RNA isolation from sera from patients with atrophic AMD (n = 10), neovascular AMD (n = 10), and age-and sex-matched controls (n = 10). A total of 377 miRNAs were coanalyzed using array technologies, and differentially regulated miRNAs were determined. Extensive validation studies (n = 90) of serum from AMD patients and controls confirmed initial results. Total RNA isolation was carried out from sera from patients with atrophic AMD (n = 30), neovascular AMD (n = 30), and controls (n = 30). Fourteen miRNAs from the discovery dataset were coanalyzed using quantitative real-time polymerase chain reaction (qRT-PCR) to validate their presence. Results: Unsupervised hierarchical clustering indicated that AMD serum specimens have a different miRNA profile to healthy controls. We successfully identified and validated the differentially regulated miRNAs in serum from AMD patients versus controls. The biomarker potential of three miRNAs (miR-126, miR-19a, and miR-410) was confirmed by qRT-PCR, with significantly increased quantities in serum of AMD patients compared with healthy controls. Conclusions: Increased quantities of miR-126, miR-410, and miR-19a in serum from AMD patients indicate that these miRNAs could potentially serve as diagnostic AMD biomarkers. All three miRNAs significantly correlated with AMD pathogenesis. Translational Relevance: The discovery of new AMD miRNA may act as biomarkers in evaluating AMD diagnosis and prognosis.