title: Handedness in twins: a meta-analysis.
abstract: In the largest meta-analysis of twins and singletons conducted to date we have found a higher incidence of left-handedness in twins compared to singletons. Our analysis revealed no difference in the frequency of left-handedness among monozygotic versus dizygotic twins. However, identical twins were more likely to be concordant for hand preference than non-identical twins, which is consistent with a genetic model of handedness. Prior analyses have not revealed these findings consistently, and this has led to a number of conflicting models of handedness.
authors.affiliation: Department of Neurology, UCLA School of Medicine, Los Angeles, CA 90095, USA.
authors.forename: N L
authors.initials: NL
authors.lastname: Sicotte
authors.forename: R P
authors.initials: RP
authors.lastname: Woods
authors.forename: J C
authors.initials: JC
authors.lastname: Mazziotta