U.S. scientists have completed a procedure that sounds like it’s straight from a Hollywood sci-fi film: editing a human’s genetic code from inside the body.
The procedure was performed Monday in California on 44-year-old Brian Madeux, a lifetime sufferer of Hunter Syndrome – a rare genetic condition that stops the body from breaking down complex molecules. These molecules then build up in the body leading to permanent and progressive damage.
Scientists injected Madeux with billions of copies of a corrective gene and CRISPR, a genetic tool for swapping his DNA around. The first results are expected within a month, but the team will know conclusively if the treatment was a success in the first three months.
In an interview with the Associated Press, Madeux said he’s humbled to be the first patient to undergo this treatment.
“It’s kind of humbling. I’m willing to take that risk. Hopefully, it will help me and other people.”
If this approach is a success, it could have a major impact on the field of gene therapy.
Previous successful approaches to alternative gene editing include altering specific DNA cells in the lab before injecting them into patients. Other approaches do not alter DNA at all.
While the implications of editing DNA from within the body are exciting, it is also a bit daunting to think that once we take this step, there’s no turning back.
Researchers have conducted extensive safety tests in animal models, and are generally positive about the results, though, every bit as cautious as they should be. As with the emergence of all brand-new technology, scientists fear there may be consequences of the procedure that we haven’t prepared for.
Madeux says that despite the risks, the potential to be free from his disease was enough to give it a try.
“I’m nervous and excited,” he stated. “I’ve been waiting for this my whole life, something that can potentially cure me.”
CRISPR gene editing works by inserting a new gene and two zinc finger proteins into a harmless virus. The virus then travels to specific cells (in the liver in this case) and penetrates them.
From there the cells begin to copy the zinc finger proteins, cutting the DNA in the process, and allowing the new gene to slip in.
Though Madeux only needs 1% of his liver cells to be corrected to be successfully cured of Hunter Syndrome, scientists are waiting on results with cautious optimism.
If the treatment is a success, the ability to alter DNA from within the body will change medicine as we know it.