"We cut your DNA, open it up, insert a gene, stitch it back up. Invisible mending," said Dr Sandy Macrae, president of Sangamo Therapeutics, the Californian company testing this for two metabolic diseases and hemophilia." Dr David R. Liu, from Harvard University, said the trial marked a new era. “The Hunter syndrome trial, led by a pioneering company, is another reminder that we have entered an era of genome editing," he said. "I’m hopeful that the approach might provide both therapeutic benefits for the patient, as well as valuable insights that inform the development of future editing therapeutics.” But Dr Robin Lovell-Badge, from the Francis Crick Institute, said getting the treatment to work on more complex conditions would be a challenge. "There's a lot of potential for treating liver diseases in this way," he said. "Taking it to more complex things like muscular dystrophy and cystic fibrosis will require a lot more work." The technique has been carried out before but previous procedures have involved cells being taken out of the body to be edited before being returned. However this is impossible to do with cells within organs like the liver, heart or brain.
Doctors at a California hospital have administered the world's first gene therapy which will alter Hunter syndrome sufferer Brian Madeux's DNA from within. Traditional treatments involve cells being removed, genetically altered and then replaced, but it doesn't work with cells in the liver, heart or brain. While it is too soon to determine whether the gene therapy, which will be triggered when it reaches Madeux's liver, has worked, if it is successful, nine patients will undergo the procedure.