The gene they added, called chrimson, comes from a single-celled algae species that is able to sense sunlight and move toward it.
A blind patient treated with a novel form of gene therapy employs a set of goggles to try to count objects placed in his field of view.
He is wearing an EEG cap so that researchers can measure his brain's response to light.
With training, the man was able to perceive whether a notebook had been placed on a table in front of him.
Optogenetics is widely used in neuroscience experiments on animals, where the light-sensing molecules are added to brain cells.
The researchers said the goggles would likely be refined and that with more training, the man might be able to see more than he does now.
“The level of vision we are going to reach is impossible to predict,” says Sahel. »
