Molecular Genomics of Glaucoma: An Update

Glaucoma is in the top five age-related eye disorders with increasing prevalence globally. Past research has led to the understanding of glaucoma as a neurodegenerative disease. Glaucoma phenomics could be syndromic or non-syndromic. Globally primary open angle, primary angle closure and primary pseudoexfoliation glaucomas are widely present. The genetics and genomics of glaucoma are heterogeneous, both clinically and genetically. Glaucoma has heritability associations, particularly with central corneal thickness, retinal nerve fibre layer and peripapillary atrophy. Ocular embryogenesis genes when mutated could cause either local (in situ), pan-ocular or systemic syndromic glaucoma phenomics. In glaucoma, except for a few single gene causes, most of the associations have been shown with innumerable gene single-nucleotide polymorphisms and epigenetic factors. The biological mechanisms in glaucoma are mechanical strain, inflammation, oxidative stress, vascular dysregulation, and immune imbalance, which independently or collectively contribute to the neurodegeneration and visual morbidity. Biomarkers in glaucoma have experimental study biases and therefore today we cannot apply them effectively in clinical practice and henceforth that demands further research to understand the fundamental basis of the disease. However, the knowledge gained in research will translate into early detection and biomolecular interventional strategies, having traction toward personalised medicine

Diabetic retinal neurodegeneration associated with synaptic proteins and functional defects: A systematic review

Diabetic retinopathy (DR) is the most common ophthalmological complication of diabetes mellitus (DM) and a leading cause of preventable visual impairment. In DM, retinal neurodegenerative changes precede microvascular changes which can be assessed by electrophysiological and advanced imaging techniques. Studies measuring retinal neurodegenerative changes in DM were systematically evaluated in this review. Included studies have assessed retinal neurodegeneration in diabetic rodents by combining clinically used diagnostic techniques and molecular assays. Significant impairment was noticed in electrophysiology data in the diabetic retina as compared to the non-diabetic retina. Also, a significant reduction in synaptic protein levels was noticed in the diabetic retina compared to the non-diabetic retina. Even though retinal neurodegeneration was noticed, no vascular abnormalities were seen in the diabetic retina. However, little is known about molecular mechanisms behind diabetic retinal neurodegeneration (DRN), which explains the need for further investigation to detect DR in the early stages of diabetes