• Genomic Clues Point to Personalized Approaches for Corneal Dystrophies

    Scientists are parsing the human genome for clues that could help tailor diagnosis and personalize treatment for patients with corneal dystrophies, said John Marshall, PhD, who presented the keynote lecture during Friday’s Refractive Surgery Subspecialty Day. “This is a very exciting time.”

    What tools are available now? Recent efforts have uncovered tools for genetic diagnosis, Dr. Marshall said. Standard surgical techniques can backfire in patients with underlying mutations, he said, so it’s critical to identify these patients in advance.

    Any refractive procedure can exacerbate an underlying genetic condition, he said. In particular, photorefractive keratectomy (PRK), LASIK, and cross-linking can upregulate the immune molecule transforming growth factor–beta and damage keratocytes in patients with underlying genetic disorders.

    Genetic testing—using a simple cheek swab—to identify mutations linked with granular corneal dystrophy types 1 and 2 is already available from Avellino Labs. The company is fine-tuning genetic tests for 3 additional dystrophies, said Dr. Marshall.  

    What genomic tools are in the pipeline? Gene therapies could eventually provide a more effective alternative to keratoplasty in patients who carry genetic mutations.

    Scientists, including Tara Moore, PhD, and her research group at Ulster University in Northern Ireland, are scrutinizing the human genome for ophthalmology-linked typos that can be corrected with CRISPR/Cas9 gene-editing technology. Thus far, the CRISPR approach has proved successful in transgenic mouse models of Meesmann epithelial corneal dystrophy, and researchers are keen to begin editing human genes.

    “Imagine, with molecular scissors, just snipping out defective base pairs,” said Dr. Marshall. “Gene therapy is on its way. We’re hoping for a first-in-human trial of some of these conditions next year.”—Anni Griswold

    Financial disclosures. Avedro: C,L,O,P; Avellino: C,L,O; Ellex: L,P; Intellectual Ventures: C,P; Schwind eye-tech-solutions: C,L.

    Disclosure key. C = Consultant/Advisor; E = Employee; L = Speakers bureau; O = Equity owner; P = Patents/Royalty; S = Grant support.