Curing Blindness with Algae

The FDA recently approved human clinical trials of a revolutionary new approach to curing blindness caused by retinitis pigmentosa (RP) – a genetic disease in which the photoreceptor cells of the retina die off. The treatment will utilize a light sensitive protein called channelrhodopsin-2, which has been used by neuroscientists for over a decade to make neurons react to light. The protein comes from single-celled green algae that technically can’t even see. Instead of an “eye” they have an “eyespot” to seek out the sunlight they need for photosynthesis. It’s these same genes which enable algae to detect light that will be transplanted into the retinas of 15 subjects in hopes of restoring their vision.

The use of gene therapy in treating genetic eye disease is not new, however, past trials have used only proteins from humans or other animals. This is the first time a trial will be conducted using plant proteins. In addition, past approaches have relied on attempting to correct the genetic defects. But RP can be caused by more than 100 different genetic defects, and identifying the correct one is problematic. This study will instead focus on “installing” new photoreceptors, thereby restoring vision regardless of which gene is responsible for the loss of vision, and making the method applicable over a broader spectrum of patients.