Scientists have, for the first time, successfully freed embryos of a piece of faulty DNA that causes deadly heart disease to run in families.
It potentially opens the door to preventing 10,000 disorders that are passed down the generations.
The US and South Korean team allowed the embryos to develop for five days before stopping the experiment.
The study hints at the future of medicine, but also provokes deep questions about what is morally right.
Science is going through a golden age in editing DNA thanks to a new technology called Crispr, named breakthrough of the year in just 2015.
Its applications in medicine are vast and include the idea of wiping out genetic faults that cause diseases from cystic fibrosis to breast cancer.
Heart stopper
US teams at Oregon Health and Science University and the Salk Institute along with the Institute for Basic Science in South Korea focused on hypertrophic cardiomyopathy.
The disorder is …