NEW

08/03/2017

Why are some people left-handed and some dexterous? Surely you've asked yourself some time. Luckily, scientists from the University of Rurh in Bochum (Germany) asked the same question ten years ago, when they began to carry out this research. After a decade of studies and analysis, scientists published their findings in the eLife journal.

That is how they realized that the answer is not only in the genes, but also that there is a great deal of responsibility in the environment that surrounds us. To reach these conclusions, the researchers had several pregnant women. They began to observe their babies from the eighth week of pregnancy until the twelfth, when the babies begin to move their limbs.

To isolate the response they were looking for, they carefully analyzed the genetic expressions in the spine, as the movements of the hands and arms begin in the motor cortex of the brain, which then sends signals to the spine to execute the movement. However, as researchers have pointed out, the motor cortex is not connected to our spine when gestation begins. But before that connection, there are already signs that indicate the preponderance towards the right or left side, hence they will examine the genes of the spine and not of the brain directly.

Although they discovered that genes determined the preponderance to one side or the other, they still lacked a detail: how much was due to the environment? They assessed it by looking at how the enzymes clustered, DNA interactions and baby feeding, and found that these causes also influenced gene expression and whether the baby would be born right-handed or left-handed.