Title:Epigenetics in Ocular Diseases
Volume: 14
Issue: 3
Author(s): Melissa M. Liu, Chi-Chao Chan and Jingsheng Tuo
Affiliation:
Keywords:
Age-related macular generation, Cataract, Diabetic retinopathy, Epigenetics, DNA methylation, microRNA.
Abstract: Epigenetics pertains to heritable alterations in gene expression that do not involve modification of the underlying
genomic DNA sequence. Historically, the study of epigenetic mechanisms has focused on DNA methylation and histone
modifications, but the concept of epigenetics has been more recently extended to include microRNAs as well. Epigenetic
patterning is modified by environmental exposures and may be a mechanistic link between environmental risk factors
and the development of disease. Epigenetic dysregulation has been associated with a variety of human diseases, including
cancer, neurological disorders, and autoimmune diseases. In this review, we consider the role of epigenetics in
common ocular diseases, with a particular focus on DNA methylation and microRNAs. DNA methylation is a critical
regulator of gene expression in the eye and is necessary for the proper development and postmitotic survival of retinal
neurons. Aberrant methylation patterns have been associated with age-related macular degeneration, susceptibility to oxidative
stress, cataract, pterygium, and retinoblastoma. Changes in histone modifications have also been observed in experimental
models of diabetic retinopathy and glaucoma. The expression levels of specific microRNAs have also been
found to be altered in the context of ocular inflammation, retinal degeneration, pathological angiogenesis, diabetic retinopathy,
and ocular neoplasms. Although the complete spectrum of epigenetic modifications remains to be more fully explored,
it is clear that epigenetic dysregulation is an important contributor to common ocular diseases and may be a relevant
therapeutic target.
