Epigenetic clocks from systemic to retinal aging: Bridging molecular insights to therapeutic innovation

Retinal aging plays a critical role in the pathogenesis of age-related ocular diseases, including age-related macular degeneration, glaucoma, and diabetic retinopathy. The epigenetic clock, an aging biomarker derived from DNA methylation patterns, has emerged as a powerful tool for investigating the mechanisms of aging. This review summarizes the applications of epigenetic clocks in assessing retinal aging, emphasizing their potential to advance the understanding of disease pathophysiology, predict disease progression, and inform therapeutic strategies. We discuss the molecular basis of epigenetic age, its relevance to retinal health, and current applications of epigenetic clocks in ophthalmic research. Furthermore, we present both epigenetic and non-epigenetic methods for biological age estimation, along with key markers of cellular senescence relevant to retinal aging studies. Finally, we highlight future research directions, including the development of retina-specific epigenetic clocks and their integration into precision medicine approaches for the treatment of retinal disorders.