In 2018 the Chinese scientist Jiankui He (pictured) made international headlines by revealing that he had messed around with the genes of an embryo in vitro, and then reinserting the embryo into a woman. The woman then gave birth to a pair of girls with genetic mutations in their CCR5 gene. He defended his action by saying that he wanted to help them fight off infection by the Human Immunodeficiency Virus, which they were in no immediate danger of contracting.
Now it turns out that far from helping the children Jiankui He may have shortened their lives. Other scientists, from the University of California, Berkeley, have scanned more than 400,000 genomes and discovered that the genetic mutation created is associated with a 21% increase in mortality between the ages of 41 and 78.
Picture source: Iris Tong