It was already known that genes have a partial role in determining handedness - studies of twins have estimated that 25% of the variation in handedness can be attributed to genes - but which genes these are had not been established in the general population.
The new study, led by researchers at the University of Oxford who were funded by the Medical Research Council and Wellcome, was published in the journal Brain. It identified some of the genetic variants associated with left-handedness by analysing the genomes of about 400,000 people from UK Biobank, which included 38,332 left-handers.
Read more (University of Oxford website)