Genetic code \'edited\' by scientists in hereditary disease breakthrough

The genetic code has been \"edited\" by scientists in a breakthrough that could lead to new treatments for some hereditary diseases. The researchers managed to persuade cells in mice to repair a faulty gene but, instead of recreating the flawed piece, the cells generated a healthy one. The faulty gene was the one responsible for haemophilia, meaning that the process cured the mouse of the hereditary condition, which can be life-threatening in humans. The scientists hope the discovery could help develop better treatments for conditions affecting the immune system, bone marrow and liver. \"Genetic editing\" works by using enzymes to unlock the DNA. A new gene could then be inserted in the right place and the DNA made to reform around it. Up to a third of genetic diseases are caused by a single faulty gene. Dr Katherine High, who led the research at the Children\'s Hospital of Philadelphia, now plans to test the treatment on larger animals. The process will not be used in human trials for around a decade. The work was published in the journal Nature. Dr Philippa Brice, of the PHG Foundation, a genetics think-tank based in Cambridge, described the research as \"very promising\".