Humanosity says…Science seems to be zeroing in on why some people have a dominant left hand. This article lays out the latest science which suggests that mutations in DNA can affect brain structure which in turn seems to determine left-handedness ….
Scientists have found the first genetic instructions hardwired into human DNA that are linked to being left-handed. The instructions also seem to be heavily involved in the structure and function of the brain – particularly the parts involved in language.
About one in ten people are left-handed and studies with twins have shown that genes have a role to play. The research also found that left-handed people may have better verbal skills as a result of the link between your dominant hand the way the brain is structured as a result.
In the left-handed participants, the two halves of the brain – the left and right hemispheres – were better connected and more coordinated in regions involved in language.
The research team at the University of Oxford used the UK Biobank which houses the fully sequenced genetic code of around 400,000 individuals and found that around 38,000 were left-handed.
The major finding of the report was to prove that there is a genetic component to left-handedness and the mechanism involved seems to be also responsible for why some snails have anticlockwise shells. However, the researchers caution that more work needs to be done to properly separate out the environmental effects from the genetic.