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Auckland University is calling for twins to take part in a study it hopes will reveal what makes a person left or right-handed.
The study will look at twins, both identical and non-identical, to see whether being left or right-handed is linked to genetics and brain asymmetry.
Professor Michael Corballis of the university's psychology department said nearly 25 per cent of identical twins were of opposite handedness, or "mirror twins", a higher level than predicted as they carry identical genetic material.
"This study will use brain images to see if there is a link between which hand is preferentially used, brain function and genetics," he said.
Of particular interest was uncovering whether mirror twins also showed mirror brain asymmetries, Professor Corballis said.
"In addition, comparing identical with non-identical twins will tell us the extent to which handedness and cerebral asymmetries are genetically controlled."
- NZPA
