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Genetic and environmental contributions to prosocial behaviour in 2- to 9-year-old South Korean twins.

Hur YM, Rushton JP - Biol. Lett. (2007)

Bottom Line: Correlational analyses showed a tendency of increasing genetic effects and decreasing shared environmental effects with age although shared family environment effects and the moderating effects of age did not attain statistical significance in model-fitting analyses.The best-fitting model indicated that 55% (95% CI: 45-64%) of the variance in the 2- to 9-year-olds' prosocial behaviour was due to genetic factors and 45% (95% CI: 36-55%) was due to non-shared environmental factors.It is concluded that genetic and environmental influences on prosocial behaviour in young South Koreans are mostly similar to those in western samples.

View Article: PubMed Central - PubMed

Affiliation: Chonnam National University, Kwangju, South Korea. maryhur@hanafos.com

ABSTRACT
Although over 50 twin and adoption studies have been performed on the genetic architecture of antisocial behaviour, far fewer studies have investigated prosocial behaviour, and none have done so on a non-western population. The present study examined mothers' ratings of prosocial behaviour in 514 pairs of 2- to 9-year-old South Korean monozygotic and dizygotic twins. Correlational analyses showed a tendency of increasing genetic effects and decreasing shared environmental effects with age although shared family environment effects and the moderating effects of age did not attain statistical significance in model-fitting analyses. The best-fitting model indicated that 55% (95% CI: 45-64%) of the variance in the 2- to 9-year-olds' prosocial behaviour was due to genetic factors and 45% (95% CI: 36-55%) was due to non-shared environmental factors. It is concluded that genetic and environmental influences on prosocial behaviour in young South Koreans are mostly similar to those in western samples.

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Related in: MedlinePlus

Sex-limited additive genetic (A), shared environment (C) and non-shared environment and measurement error (E) effects on the scores of the prosocial scale of opposite-sex DZ twin pairs. Subscripts m and f refer to male and female, respectively. rg, genetic correlations; PS, prosocial scale; M, moderator (age); β, regression coefficient for M.
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fig1: Sex-limited additive genetic (A), shared environment (C) and non-shared environment and measurement error (E) effects on the scores of the prosocial scale of opposite-sex DZ twin pairs. Subscripts m and f refer to male and female, respectively. rg, genetic correlations; PS, prosocial scale; M, moderator (age); β, regression coefficient for M.

Mentions: Although the results can be gleaned from the correlational analyses, we also carried out model fitting to yield parameter estimates and compare alternative models (Plomin et al. 2001). We used a general sex-limitation model incorporating age as a moderator (figure 1; Neale & Cardon 1992; Purcell 2002). The full model included additive genetic (A) and shared (C) and non-shared (E) environmental factors that were allowed to differ as a function of sex and age (M). The extent to which age moderates A, C and E was represented by βa, βc and βe, respectively. The main effects of age were also included in the model for males (μ+βmM) and females (μ+βfM). On the basis of the degree of genetic relatedness, the correlations for A were set at 1.0 for MZ twins, at 0.50 for same-sex DZ (SSDZ) twins and at less than 0.50 for OSDZ twins. The correlation for C was set at 1.0 for all types of twins because they were raised together. The correlation for E was set at 0.0 because this variance is unique to each member of a twin pair.


Genetic and environmental contributions to prosocial behaviour in 2- to 9-year-old South Korean twins.

Hur YM, Rushton JP - Biol. Lett. (2007)

Sex-limited additive genetic (A), shared environment (C) and non-shared environment and measurement error (E) effects on the scores of the prosocial scale of opposite-sex DZ twin pairs. Subscripts m and f refer to male and female, respectively. rg, genetic correlations; PS, prosocial scale; M, moderator (age); β, regression coefficient for M.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC2117382&req=5

fig1: Sex-limited additive genetic (A), shared environment (C) and non-shared environment and measurement error (E) effects on the scores of the prosocial scale of opposite-sex DZ twin pairs. Subscripts m and f refer to male and female, respectively. rg, genetic correlations; PS, prosocial scale; M, moderator (age); β, regression coefficient for M.
Mentions: Although the results can be gleaned from the correlational analyses, we also carried out model fitting to yield parameter estimates and compare alternative models (Plomin et al. 2001). We used a general sex-limitation model incorporating age as a moderator (figure 1; Neale & Cardon 1992; Purcell 2002). The full model included additive genetic (A) and shared (C) and non-shared (E) environmental factors that were allowed to differ as a function of sex and age (M). The extent to which age moderates A, C and E was represented by βa, βc and βe, respectively. The main effects of age were also included in the model for males (μ+βmM) and females (μ+βfM). On the basis of the degree of genetic relatedness, the correlations for A were set at 1.0 for MZ twins, at 0.50 for same-sex DZ (SSDZ) twins and at less than 0.50 for OSDZ twins. The correlation for C was set at 1.0 for all types of twins because they were raised together. The correlation for E was set at 0.0 because this variance is unique to each member of a twin pair.

Bottom Line: Correlational analyses showed a tendency of increasing genetic effects and decreasing shared environmental effects with age although shared family environment effects and the moderating effects of age did not attain statistical significance in model-fitting analyses.The best-fitting model indicated that 55% (95% CI: 45-64%) of the variance in the 2- to 9-year-olds' prosocial behaviour was due to genetic factors and 45% (95% CI: 36-55%) was due to non-shared environmental factors.It is concluded that genetic and environmental influences on prosocial behaviour in young South Koreans are mostly similar to those in western samples.

View Article: PubMed Central - PubMed

Affiliation: Chonnam National University, Kwangju, South Korea. maryhur@hanafos.com

ABSTRACT
Although over 50 twin and adoption studies have been performed on the genetic architecture of antisocial behaviour, far fewer studies have investigated prosocial behaviour, and none have done so on a non-western population. The present study examined mothers' ratings of prosocial behaviour in 514 pairs of 2- to 9-year-old South Korean monozygotic and dizygotic twins. Correlational analyses showed a tendency of increasing genetic effects and decreasing shared environmental effects with age although shared family environment effects and the moderating effects of age did not attain statistical significance in model-fitting analyses. The best-fitting model indicated that 55% (95% CI: 45-64%) of the variance in the 2- to 9-year-olds' prosocial behaviour was due to genetic factors and 45% (95% CI: 36-55%) was due to non-shared environmental factors. It is concluded that genetic and environmental influences on prosocial behaviour in young South Koreans are mostly similar to those in western samples.

Show MeSH
Related in: MedlinePlus