Eye, Before and after Gene Therapy (image) University of Pennsylvania Share Print E-Mail Caption A view of the eye of a dog affected by the canine equivalent of Best disease before (left) and 5 years after (right) the gene therapy underscores how the treatment reversed a sizeable lesion--and lasted. The black mark visible on the treated eye is the injection site. Credit University of Pennsylvania Usage Restrictions In context of reporting Share Print E-Mail Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.