While there's no righty or lefty gene, DNA does seem to play a role in handedness. In a recent study published in Brain: A Journal of Neurology, researchers at the University of Oxford looked at the DNA of about 400,000 people in the U.K. and found that four regions of the genome are generally associated with left-handedness. Three out of these four regions were involved in brain development and structure. Some researchers hope that studying the biological differences between lefties and righties could shed light on how the brain develops specializations in its right and left hemispheres... Righties have dominated...