We Are This Close to "Designer Babies"

On February 1, scientists from the United Kingdom's Francis Crick Institute got the okay to start research on human embryos using a new genome editing technology called CRISPR. Their work, which will mark only the second time CRISPR has been applied to humans, will use embryos to try to understand the very early stages of human development and pinpoint the genes causing miscarriages and fetal defects.

Not surprisingly, the Crick project has reignited a firestorm of debate over the ethics of human gene editing. "This is the first step in a well mapped-out process heading to genetically modified babies, and a future of consumer eugenics," said Dr. David King, director of Human Genetics Alert, in response to the news. 

CRISPR is essentially a cellular scalpel. The small enzyme works by moving through the body's cells and cutting away at precise pieces of the genome—something that's never before been possible to do with such efficiency and ease. Since 2012, it's been used to cut out the gene mutations leading to HIV and sickle cell anemia. Last spring...