Scientists for the first time have tried editing a gene inside the body in a bold attempt to permanently change a person's DNA to cure a disease. The experiment was done Monday in California on 44-year-old Brian Madeux, the AP reports. Through an IV, Madeux, who has a metabolic disease called Hunter syndrome, received billions of copies of a corrective gene and a genetic tool to cut his DNA in a precise spot. Those with Madeux's condition lack a gene that makes an enzyme that breaks down certain carbohydrates, which build up and wreak havoc. Madeux has had 26 operations for hernias, bunions, bones pinching his spinal column, and ear, eye, and gall bladder problems. Scientists have edited genes before by altering cells in the lab. There are also gene therapies that don't edit DNA. But these methods can only be used for a few diseases, and some have results that may not last; others can't control where the DNA is inserted.
This time the gene tinkering, which uses a tool called zinc finger nucleases, is happening in a precise way inside the body. "It becomes part of your DNA and is there for the rest of your life," says the head of a company testing the therapy. That also means there's no way to erase editing mistakes. "You're really toying with Mother Nature," and the risks can't be fully known, but the studies should move forward because these are incurable diseases, says another expert. The damage Madeux has already suffered can't be fixed, but he hopes therapy will stop the need for expensive weekly enzyme treatments. Signs of whether the procedure is working may come in a month; tests will show for sure in three months. "It's kind of humbling" to be the first to test this, Madeux says. "I've been waiting for this my whole life."