Scientists test algae for potential cure for blindness

It may sound far out, but tests are about begin to see if a protein from algae could help cure blindness in humans. Found in dirt and water, the single-cell green algae is known as Chlamydomonas reinhardtii, and its eyespot, used to find sunlight for photosynthesis, contains the protein channelrhodopsin-2. This protein is sensitive to light in a way similar to the human eye, and scientists as the company RetroSense have been given FDA approval for clinical trials to inject it into the retina of the blind, with the hope it could one day lead to a cure.

Channelrhodopsin-2 has already proven itself beyond valuable in neuroscience, being used to get neurons to respond to light, something they don't normally do at all. This lead to optogenetics, where scientists can probe brain circuits with light after the protein has been encoded into neurons.

Since channelrhodopsin-2 has been so successful in the brain, RetroSense want to try using optogenetics in the human eye for the first time ever. 15 people blinded by retinitis pigmentosa, a genetic disease, have signed up for the clinical trial, which RetroSense hopes to begin by the end of the year.

The rods and cones of the human eye are the cells normally sensitive to light, but the tests will see the channelrhodopsin-2 gene injected into the neurons of the inner retina. Previous gene therapy trials have tried to restore sight by injecting a normal copy of a gene to make up for a faulty one. But what makes RetroSense's strategy so significant is that the gene is coming from an alga, something radically different from another human or even another animal.