CRISPR partially restores vision in people with color blindness
For the first time, scientists have used CRISPR to modify DNA inside a person’s eye.
CRISPR has been praised for its ability to alter DNA sequences in cells. But, until recently, these cells had to be removed from the body and altered in a lab, then somehow re-injected.
But modifying an otherwise healthy cell while it’s still in the human body allows scientists to cure diseases caused by genetic mutations in organs they would not otherwise have been able to access, including eye problems.
The challenge: Carlene Knight suffered from a rare genetic condition called Leber’s congenital amaurosis. It primarily affects the retina and is the most common cause of inherited blindness, affecting nighttime, fine detail and color vision.
Knight described the condition to The daily beast like “extreme tunnel vision”.
“I compare it to looking through a window with a little hole and trying to find something like a building outside.”
People born with the genetic condition face progressive vision loss throughout their lives, sometimes going completely blind.
“I wanted to help children whose lives could be improved by seeing. “
DNA binding: In a study conducted by Editas Medicine and Oregon Health & Science University, seven volunteer patients were treated with the new therapy, which provides CRISPR gene editors in the body to correct mutations in the cell nucleus.
Of the seven, two received low doses, two received high doses and three received medium doses.
Knight was one of three who received the medium dose.
“When I was told about the trial, I was really excited because I wanted to help children whose lives could be improved through vision,” Knight said. Recount The daily beast. “The hope is that if they undergo the procedure early enough, they will have a lot more vision later. [sic] life, as their neural pathways develop.
“Just amazing”: The study changed Knight’s life. Before, she bumped, barely able to navigate her surroundings. But now she can see more objects, shapes and even revisit colors. His vision is brighter and clearer.
“It’s good. I don’t scare people and I don’t have as many bruises on my body,” Knight Recount NPR.
“I have always liked the colors. Ever since I was a kid, it’s one of those things that I could enjoy with just a small amount of vision. But now I realize how much brighter they were when I was a kid because I can see them a lot brighter now, ”she says. “It’s just amazing.”
To celebrate, Knight dyed her hair green – her favorite color.
The caveats: The first results of the study are promising. But the survey has so far only had seven participants, and not all have benefited. There is still work to be done to ensure that it is safe and effective, including increasing the number of participants.
However, because the initial study was positive, the researchers were allowed to enroll more people in a second round of trials.
Gene therapy for vision loss has continued to innovate – with gene therapy using viral vectors showing promise for glaucoma, restoring young retinal cells and even curing retinitis pigmentosa.
The addition of CRISPR to the mix and the ability to use it directly in the body marks a milestone for therapy for vision loss, but also for difficult-to-treat genetic conditions as a whole.
In the meantime, Knight’s vision continues to improve.
“It will be good if I can see my granddaughter playing and riding a bike and stuff like that,” she told the Daily Beast. “I hope one day I can read him a children’s book, in large print. It would be really good. “
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