An Oxford University study reveals why some people prefer the left to the right. According to the researchers, it would be due to some genetic regions that influence the architecture of the brain. Furthermore, the left-handed genes could influence the way the brain areas dedicated to language work.
The role of DNA in the choice of the dominant hand is not new: previous studies had attributed 25% of causality to genes. Nevertheless, it was still unclear which genes were involved. For this reason, the team of Dr. Akira Wiberg examined the genes of 400,000 people. Of these, 38,332 were left-handed. Analyzes revealed common genetic variants among left-handed people, located in four different genetic regions. Three of these code for proteins related to brain development, also affecting microtubule development.
The structures in question are among the elements that determine how the body's cells will develop. Later, the researchers analyzed the brain imaging of about 10,000 subjects. This allowed them to examine variations in the brain structure of left-handed people. From what has emerged, in those who use the left the two hemispheres communicate better.
This could facilitate the mental processes related to language, even if to confirm it further tests will be needed. Within the examined sample, differences also emerged with regard to the chances of getting sick. Left-handers have a slightly lower risk of getting Parkinson's and a little more schizophrenia.