A new study has handed important information to scientists mystified by lefties and righties. Why do people favor one hand over the other? The trait has baffled scientists across a half-century of scattershot research. While environmental factors appear to play a crucial role, many scientists have long espoused a theory that a single dominant gene may be the reason so many people are right-handed. But in new studies encompassing millions of people, scientists now are discovering that the answer may lie in dozens of genetic...

Source: Wall Street Journal October 12, 2020 15:45 UTC