There is a gene related to the formation of cells that can offer insights into the reasons why some people are left-handed. The conclusion is a study published this Tuesday in scientific journal Nature Communications.
Studies indicate that around 10% of the world’s population – a group that includes personalities such as Lady Gaga, Barack Obama, Paul McCartney or Justin Bieber – will be “left-handed” or “left-handed”. That is: 10% of people have greater ability with the left side of the bodyespecially with the hand and this new research helps to try to understand why.
Researchers have identified rare genetic variants involved in controlling cell formation and found that they are 2.7 times more common in left-handed people. There is a gene called “TUBB4B”, which, scientists believe, will influence the development of the brain asymmetry that determines which hand will be dominant. of a person
“In most people, it is the left hemisphere that controls the dominant right hand. Nerve fibers pass from the left to the right side in the lower region of the brain. In left-handed people, it is the right hemisphere that is in control of the dominant hand ”, explains Clyde Francks, scientist at the Max Planck Institute for Psycholinguistics, in the Netherlands, and one of the authors of the study, cited by Reuters.
The TUBB4B gene controls the protein that enters the filaments that guarantee the internal structure of cells. And the rare genetic mutations in TUBB4B are more common in left-handerswhich suggests that these filaments are involved in the way the brain defines asymmetries.
The discovery is based on genetic data from more than 350,000 British adults, available in the UK Biobank database. Around 11% of the sample participants were left-handed
Discovery may have applications in other scientific fields
This research, says Clyde Francks, may also have relevance in the field of psychiatrysince diseases such as schizophrenia are twice as common in left-handed or ambidextrous people (who have equal ability in both their left and right hands) and three times more common in people with autism.
Even so, the researcher emphasizes that this genetic influence corresponds to a very small fraction (around 0.1%) of what leads someone to be left-handed and that the determination of the dominant hand can be, for most people, the result of chance. .
“We believe that, in most cases, someone becomes left-handed simply because of random variations during embryonic brain development,” says Clyde Francks. “For example, random changes in the concentration of certain molecules.”
The prevalence of left-handed people also varies, notes the scientist, depending on the region of the world. In Africa, Asia and the Middle East, the percentages are lower than, for example, in Europe and North America – which, he argues, may reflect the suppression of left-handedness in some cultures, where children are forced to learning to write with your right hand.
