Genome sequencing has lead researchers to identify the root cause of posterior polymorphous corneal dystrophy (PPCD), a rare autosomal-dominant form of corneal dystrophy that affects the corneal endothelium, according to a new study published in the March edition of the American Journal of Human Genetics.1 Investigators from University College London’s Institute of Ophthalmology and Moorfields Eye Hospital London have nailed down the precise variation to the DNA—located on a gene called GRHL2—that leads to dysfunction in the endothelial barrier and, ultimately, PPCD.1

Using data from a large family of Czech origin, the researchers mapped a locus for an autosomal-dominant corneal endothelial dystrophy. The whole-genome sequencing identified a unique variant that causes the gene to be expressed inappropriately in corneal endothelial cells.

“We are delighted that the results from this study led to the discovery of a new genetic cause of PPCD. This will be the foundation for further studies to understand even more about the biological processes leading to corneal dystrophies and to developing new treatments,” Neil Meemaduma, a research manager with Fight for Sight—which assisted in funding the research—said in a statement on the organization’s website.2

1. Liskova P, Dudakova L, Evans C, et al. Ectopic GRHL2 Expression Due to Non-coding Mutations Promotes Cell State Transition and Causes Posterior Polymorphous Corneal Dystrophy 4. AJHG. 2018;102(3):447–59.

2. Omoniyi Y. Researchers discover a new genetic cause of corneal dystrophy. Fight for Sight: The Eye Research Charity.