Suppose you’re a basketball star who wants to build up old, tired muscles. Would you try gene doping—the injection of genes that could bulk you up?
Or suppose you plan to have a baby. Would you genetically design your baby to look a certain way?
Neither is possible yet, but they’re not far off. Genetic engineering—making changes in genetic material—has already had a huge impact on our world. It can do good things, but it also raises some hard questions.
