Are There Genes for Intelligence — And Is It Racist to Ask?

Some people are taller than others. Others have wider hips, lighter hair, longer toes, or flatter feet. No one disputes that our genes help determine how we look. But what about intelligence—is it an inherited trait?

And as our ability to tinker with the genomes of human embryos comes closer to reality, will creating babies with enhanced intelligence be far behind?

Before taking that leap, we would have to understand the genes that contribute to intelligence. Some scientists are on the hunt for such “smart genes,” and their research has come under fire. The two biggest specters: that the work could support racist notions of biological differences, and that it could make those designer smart babies a reality.

That’s why scientists are now being called upon to consider whether it’s ethical to study the genetics of intelligence. Researchers should think about “limits we should place or steps we can take to be sure we don't repeat historical errors,” such as forced sterilization of the “feeble-minded” in the early 20th century, said Mildred Solomon, president of the Hastings Center, a bioethics...