Mutational Screening for Mitochondrial tRNA Mutations in 150 Children with High Myopia

Abstract

Background: Myopia is a very common eye disease with an unknown etiology. Increasing evidence shows that mitochondrial dysfunction plays an active role in the pathogenesis and progression of this disease. Objectives: The purpose of this study was to analyze the relationship between mitochondrial tRNA (mt-tRNA) variants and high myopia (HM). Methods: The entire mt-tRNA genes of 150 children with HM, as well as 100 healthy subjects, were PCR-amplified and sequenced. To assess the pathogenicity, we used the phylogenetic conservation analysis and pathogenicity scoring system. Results: We identified six candidate pathogenic variants: tRNALeu (UUR) T3290C, tRNAIle A4317G, tRNAAla G5591A, tRNASer (UCN) T7501C, tRNAHis T12201C, and tRNAThr G15915A. However, these variants were not identified in controls. Further phylogenetic analysis revealed that these variants occurred at the positions, which were very evolutionarily conserved and may have structural-functional impacts on the tRNAs. Subsequently, these variants may lead to the impairment of mitochondrial translation and aggravated mitochondrial dysfunction, which play an active role in the phenotypic expression of HM. Conclusions: Our results suggested that variants in mt-tRNA genes were the risk factors for HM, which provided valuable information for the early detection and prevention of HM.