Media release
8 October 2008
The genetics of handedness and cerebral asymmetry
New research is looking at whether being right handed is due to genetics or other factors.
A new study at The University of Auckland is looking for pairs of twins, both identical and non-identical, to take part
in a study looking at whether handedness (ie being left- or right-handed) is linked to genetics and brain asymmetry.
“Nearly 25% of identical twins are of opposite handedness, or mirror twins, a higher level than predicted as they carry
identical genetic material,” says Professor Michael Corballis of the University’s Department of Psychology. “This study
will use brain images to see if there is a link between which hand is preferentially used, brain function and genetics.”
The study will look at identical twins and non-identical twins compared to singly born ‘controls’, using magnetic
resonance imaging (MRI) to investigate brain asymmetries in twins and how these relate to handedness. The MRI will
provide information on both structural (anatomical differences in the brains) and functional (areas of brain activity
during language processing) asymmetries which will help determine which side of the brain is used for language and
spatial skills.
“It is of particular interest to uncover whether mirror twins also show mirror brain asymmetries,” continues Professor
Michael Corballis. “In addition, comparing identical with non-identical twins will tell us the extent to which
handedness and cerebral asymmetries are genetically controlled.”
The study is funded by the Marsden Fund, administered by the Royal Society of New Zealand.
Volunteers in the study will need to attend a brain imaging session at the Centre for Advanced Magnetic Resonance
Imaging at the University’s Grafton Campus. For more information on participating in the study, contact 09 373 7599 ext
88561 or ext 88515, m.corballis@auckland.ac.nz.
ENDS