A Review of Personalised Molecular Medicine for the Treatment of Corneal Disorders

The cornea represents an ideal tissue to elucidate the potential of molecular medicine to treat genetic disorders. It is a small, readily accessible tissue that is easy to monitor treat topically, while a number of corneal disorders are well characterized with regard to a known genetic cause. In addition, due to their genetic basis most of these conditions are bilateral, affecting
both corneas, allowing for a clear comparison between treated and untreated tissue using the fellow eye as a control. Currently, molecular techniques utilising siRNAs, CRISPR/Cas9, TALENS and ZFNs are being evaluated by many for their therapeutic potential for corneal disorders. Methodologies are discussed within this review with particular emphasis on the more recent and emerging field of CRISPR/Cas9-based therapeutics. Since the advent of gene therapies, effective delivery has been a challenge. Potential ocular delivery techniques include viral vectors, nanoparticles or physical injection. Studies employing in vitro and in vivo models of corneal disorders have demonstrated promising results for treatment by molecular techniques. However, many of these studies have not translated into the clinic, perhaps due to a lack of good animal
models for preclinical testing or failure to develop suitable delivery methods. Until this occurs it is difficult to fully gauge the usefulness of these techniques to treat corneal disorders in human patients over a sustained time period.
Here we present a review of current research into molecular-based therapies for genetic corneal disorders and discuss the applicability of these studies to advancing translational research for other genetic disorders.