He Jiankui, associate professor at the Southern University of Science and Technology of China, speaks during a panel discussion at the Second International Summit on Human Genome Editing in Hong Kong, China, on Wednesday, Nov. 28, 2018. He, the Chinese researcher who says he altered the genes of a pair of twin girls, stood by his work Wednesday and revealed a second pregnancy has resulted from the procedure amid growing condemnation of the controversial project. Photographer: Anthony Kwan/Bloomberg via Getty Images
