A pioneering treatment to correct errors in DNA, has transformed the lives of six boys with a deadly genetic disease, doctors declare. For people suffering Wiskott-Aldrich syndrome (WAS), a defective immune system leaves people susceptible to infections and bleeding.
A British and French study, published in JAMA, has used tamed HIV to correct the irregularities. A child wheelchair-user now has free mobility and there are improvements in other cases. The syndrome affects up to 10 children in every 1 million, almost exclusively boys.
Patients suffering the condition find that tiny bumps and scrapes can lead to wounds that are slow to close. Eczema is often present and they face repeat infections including pneumonia as well as some cancers and autoimmune diseases. It arises from an error in the genetic code that contains the building instructions for a key element in the immune system, a protein called WAS. The main therapy is bone marrow transplant; however that can only be considered when the donor is a close tissue match, such as from a sibling.
Great Ormond Street Hospital, in London, and Necker Children’s Hospital, in France have conducted trials to remove a part of the children’s bone marrow and purify it to find the cells that regenerate the immune system. Afterwards, the corrected bone marrow cells were then inserted back in the children. The outcome was so positive that in six out of seven boys, the therapy was a success. It reversed symptoms and drastically cut the number of nights spent in hospital.
Daniel Wheeler, who is now 15 and from Bristol, was the first British patient. His older brother died from the same condition when he was two-and-a-half. Their mum Sarah told the BBC News website: “Daniel was in and out of hospital, he had frequent infections of ear, chest, flare-ups and bruised joints, and lots of operations.”
Prof Adrian Thrasher, from Great Ormond Street Hospital, told the BBC News website: “I think it is very significant, it is another clear and powerful demonstration that a gene therapy approach is an effective one.” Prof Ian Alexander from the Gene Therapy Research Unit at Sydney’s Children’s Medical Research Institute in Australia said although the work was promising, it was “still early days”.
When all medicine, even Paracetamol, has risks, couldn’t interfering with genetic code bring huge dangers? Several trials have been abandoned as patients developed leukaemia when the modification turned healthy cells cancerous. But those trials did show one thing – the underlying principle worked. Could gene therapy be about to come in from the cold?