Sat | Sep 21, 2019

Left-handed genes now identified, say scientists

Published:Wednesday | September 11, 2019 | 12:17 AM
Left hand
Left hand

Recent research has now identified the genetic differences associated with left-handedness, a trait found in 10 per cent of the human population.

According to scientists, those genetic variants result in differences in brain structure, which might mean that left-handed people have better verbal skills than the right-handed majority.

While previous research into twins has indicated that genes are at least partially responsible for controlling handedness, the new study, conducted by scientists from the University of Oxford and published in the journal Brain, is the first to identify which genetic variants separate the lefties from the righties.

The research could suggest a potential correlation between left-handedness and superior verbal skills, said Akira Wiberg, a Medical Research Council fellow at the University of Oxford who worked on the study.

“This raises the intriguing possibility for future research that left-handers might have an advantage when it comes to performing verbal tasks, but it must be remembered that these differences were only seen as averages over very large numbers of people and not all left-handers will be similar,” he said in a news release.

Further research must be conducted to test this potential advantage, according to Gwenaëlle Douaud, joint senior author of the study and a fellow at Oxford’s Wellcome Centre for Integrative Neuroimaging.

“We need to assess whether this higher coordination of the language areas between left and right side of the brain in the left-handers actually gives them an advantage at verbal ability. For this, we need to do a study that also has in-depth and detailed verbal-ability testing,” she said.

Funded by the UK’s Medical Research Council and Wellcome, a UK medical research charity, the researchers studied the DNA of 400,000 people, including 38,332 left-handers, from the UK Biobank, a database comprising the health information of volunteers across the country.

The study also indicated an association between the aspects of brain development linked to handedness and the likelihood of developing schizophrenia or Parkinson’s disease.

The researchers stressed, however, that the association between handedness, schizophrenia and Parkinson’s indicates only correlation, not causation, and that the difference in terms of the number of people with the illnesses is very slight.