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Handedness and Eye-dominance: A Meta-analysis of Their Relationship

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About one in ten people is left-handed and one in three is left-eyed. The extent of the association of handedness and eyedness is unclear, as some eyedness measures are potentially contaminated by measures of handedness. A meta-analysis of hand-eye concordance in 54,087 subjects from 54 populations, found that concordance was 2.69 x greater in questionnaire rather than performance studies, 1.95 x greater in studies using unimanual monocular performance measures, and 6.29 x greater in studies using non-sighting measures of eye-dominance. In the remaining studies, which seemed to show no evidence of bias, the odds-ratio for hand-eye concordance was 2.53 x; in a population with 9.25% left-handedness and 36.53% left-eyedness, 34.43% of right-handers and 57.14% of left-handers are left-eyed. This pattern of hand-eye association poses problems for genetic models of cerebral lateralisation, which must invoke pleiotropic alleles at a single locus or epistatic interactions between multiple loci. There was no evidence that the incidence of eyedness, or the association between eyedness and handedness, differed between the sexes.
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... All transformed items showed positive correlations on the phenotypic level. Previous research has shown a tendency towards a higher probability of left-sided lateral preferences in left-handers [28,73], suggesting that a common dimension of asymmetry underlies hand, foot, and eye preference [74]. Multivariate SEM analysis supported the presence of one shared genetic factor explaining variance in handedness, footedness, and eyedness, but no unique genetic factors explaining independent variance for individual phenotypes in ALSPAC and the Hong Kong cohort. ...
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Handedness is the most commonly investigated lateralised phenotype and is usually measured as a binary left/right category. Its links with psychiatric and neurodevelopmental disorders prompted studies aimed at understanding the underlying genetics, while other measures and side preferences have been less studied. We investigated the heritability of hand, as well as foot, and eye preference by assessing parental effects (n ≤ 5028 family trios) and SNP-based heritability (SNP-h2, n ≤ 5931 children) in the Avon Longitudinal Study of Parents and Children (ALSPAC). An independent twin cohort from Hong Kong (n = 358) was used to replicate results from structural equation modelling (SEM). Parental left-side preference increased the chance of an individual to be left-sided for the same trait, with stronger maternal than paternal effects for footedness. By regressing out the effects of sex, age, and ancestry, we transformed laterality categories into quantitative measures. The SNP-h2 for quantitative handedness and footedness was 0.21 and 0.23, respectively, which is higher than the SNP-h2 reported in larger genetic studies using binary handedness measures. The heritability of the quantitative measure of handedness increased (0.45) compared to a binary measure for writing hand (0.27) in the Hong Kong twins. Genomic and behavioural SEM identified a shared genetic factor contributing to handedness, footedness, and eyedness, but no independent effects on individual phenotypes. Our analysis demonstrates how quantitative multidimensional laterality phenotypes are better suited to capture the underlying genetics than binary traits.
... The papers published in the first issue of Laterality investigated the relationship between handedness and eye-dominance (Bourassa, 1996), attempts to switch the writing hand (Porac, 1996), handedness in professional cricket players (Edwards & Beaton, 1996), and the magnitude of laterality effects and sex differences in functional asymmetries (Voyer, 1996), all topics still of interest today, as shown by recent papers published in Laterality on handedness (e.g., Bruckert, Thompson, Watkins, Bishop, & Woodhead, 2021;Papadatou-Pastou et al., 2021;Tzourio-Mazoyer, Labache, Zago, Hesling, & Mazoyer, 2021) and cognitive sex differences (e.g., Hirnstein, Hugdahl, & Hausmann, 2019). ...
... and earedness, although the direction of these preferences was less consistent than that of handedness (60-70%, Bourassa, 1996;Saudino & McManus, 1998). Such subtle asymmetries have been found not only for the use of body parts but also for more complex behaviour, such as choosing an item (Wilson & Nisbett, 1978), posing for portraits (e.g., McManus & Humphrey, 1973;Nicholls, Clode, Wood, & Wood, 1999), choosing a seat (e.g., Karev, 2000;Okubo, 2010), cradling (e.g., Manning & Chamberlain, 1991), and kissing (e.g., Güntürkün, 2003). ...
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... Likewise, people also have their dominant eyes and about one third people are left-eyed [40]. Bourassa et al. [41] conducted a meta-analysis to investigate the association between handedness and eye-dominance. The meta-analysis includes 54,087 subjects from 54 independent studies, each summarized by a 2 × 2 table recording counts of being "left-handed, left-eyed", "lefthanded, right-eyed", "right-handed, left-eyed", and "right-handed, right-eyed". ...
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