A gene-editing therapy successfully treated sufferers of a debilitating disorder. Hereditary angioedema causes attacks of crippling swelling, and can be fatal, especially if it closes the throat and obstructs breathing. It is largely caused by a fault in a gene for a particular enzyme. The new treatment replaces the faulty gene in patients’ cells, and led to a 95% reduction in attacks in a preliminary trial. The gene-editing technique CRISPR, which the new treatment uses, has long been usable on embryos, but recent breakthroughs have seen it used in adults and children, which involves getting it into all the relevant cells in a body. In November, the U.K. became the first country to approve a CRISPR drug, targeting two blood diseases including sickle-cell anemia. |