"The first volunteer was a 58-year-old French man who began going blind 40 years ago. When the experiment started, he could sense light but could not distinguish shapes. He received an injection in his worse eye of a harmless virus called an adeno-associated virus, which carried the gene for an opsin from algae. The researchers waited a few months for the ganglion cells in the patient’s eye to begin to produce the new protein. Then they began to train him to use special goggles that amplify incoming light from an image and focus it on the retina in the amber wavelength sensed by the opsin.
Within a few months, the man reported he could see the white stripes at a pedestrian crossing while walking outside wearing the goggles..."
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