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A STUDY OF THE HERITABILITY OF INTELLIGENCE IN SUDAN
Howida Sirelkhatim Abdalrahim Toto1, Davide Piffer2, Omar Haroun Khaleefa3
1*Sudan University of Science & Technology,Sudan.
Journal of Biosocial Science
|May 24, 2018
Summary
This study found that shared environmental factors, not genetics, significantly influence intelligence in 10-year-old Sudanese twins. Environmental influences accounted for over 59% of the variance in cognitive abilities.
Area of Science:
- Behavioral Genetics
- Developmental Psychology
- Cognitive Science
Background:
- Understanding the genetic and environmental contributions to intelligence is crucial for educational and developmental interventions.
- Twin studies are a powerful tool for disentangling heritability and environmental influences on complex traits.
- Previous research indicates varying heritability estimates for intelligence across different populations.
Purpose of the Study:
- To investigate the relative contributions of genetic and environmental factors to intelligence in a Sudanese child population.
- To estimate the heritability of intelligence using twin data.
- To assess the impact of shared environmental influences on cognitive abilities.
Main Methods:
- A sample of 316 monozygotic (MZ) and 550 same-sex dizygotic (DZ) twins, with a mean age of 10 years, was recruited in Sudan.
- Intelligence was assessed using the Standard Progressive Matrices (SPM), a non-verbal reasoning test.
- Standard biometric models were applied to estimate genetic and environmental variance components.
Main Results:
- Heritability of intelligence was estimated at a low value of 0.172.
- Shared environmental influences explained a substantial portion of the variance in intelligence, estimated at 0.596.
- Non-shared environmental influences accounted for the remaining variance.
Conclusions:
- Environmental factors play a dominant role in shaping intelligence among Sudanese children in this cohort.
- Genetic influences on intelligence appear to be less significant in this specific population compared to environmental factors.
- Findings highlight the importance of environmental enrichment and support for cognitive development in Sudan.
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