Blind woman may see thanks to gene therapy and light

Optogenetics are getting their first proper test in humans.


Optogenetics, or mixing gene therapy with light treatments, is finally getting a proper field test: doctors have given a blind Texas woman the first optogenetics-based therapy in hopes of restoring some of the vision lost to a degenerative retina disease. The procedure injected her eye with viruses containing DNA from light-sensitive algae, letting them mimic the eye's rods and cones by generating electricity whenever they're subjected to light. The patient won't get full vision even if the therapy is a runaway success, but it could be enough to let her know when there's nearby activity.

Whether or not this works is far from certain. Doctors are going to watch the woman's progress closely over the next year, and she may need up to three more treatments. The cells also can't adjust their light sensitivity the way a retina can, so a truly effective system might need video glasses that automatically tweak the image brightness as the wearer ventures indoors or outdoors. Even so, this promises to be a breakthrough -- it's less intrusive than the current solution, which implants a chip that stirs cell activity. Eventually, certain forms of blindness may be relatively easy to mitigate.