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No association between dopamine D2 receptor gene (DRD2) and human intelligence
H W Moises1, R M Frieboes, P Spelzhaus
1Department of Psychiatry, Kiel University Hospital, Federal Republic of Germany. moises@psychiatry.uni-kiel.de
Journal of Neural Transmission (Vienna, Austria : 1996)
|March 23, 2001
Summary
This study investigated the dopamine D2 receptor gene (DRD2) for its role in general cognitive ability (g). Researchers found no significant association, suggesting DRD2 is unlikely to be a major factor in cognitive ability.
Area of Science:
- Neuroscience
- Genetics
- Psychology
Background:
- Intellectual functioning, assessed by IQ tests, is a complex trait influenced by genetic and environmental factors.
- Studying extremes of IQ distribution (high vs. average) can reduce confounding variables in genetic association studies.
- The dopamine D2 receptor gene (DRD2) was a candidate for general cognitive ability (g) due to its link with visuospatial ability.
Purpose of the Study:
- To investigate the association between the dopamine D2 receptor gene (DRD2) and general cognitive ability (g).
- To utilize a contrast of extremes approach comparing high and average IQ adults.
Main Methods:
- Employed a contrast of extremes design comparing adults with high IQ (N=71) and average IQ (N=78).
- Conducted association studies focusing on the dopamine D2 receptor gene (DRD2) as a candidate for general cognitive ability (g).
Main Results:
- No significant differences were found in the association between the DRD2 gene and general cognitive ability (g) between the high and average IQ groups.
- These findings align with two previous studies in children, further weakening the hypothesis.
Conclusions:
- The dopamine D2 receptor gene (DRD2) is unlikely to play a significant role in general cognitive ability (g).
- Three negative studies collectively indicate a minimal contribution of DRD2 to cognitive ability.
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