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Low digit ratio 2D:4D in alcohol dependent patients
Johannes Kornhuber1, Gabriele Erhard, Bernd Lenz
1Department of Psychiatry and Psychotherapy, Friedrich-Alexander University of Erlangen-Nuremberg, Erlangen, Germany. Johannes.kornhuber@uk-erlangen.de
Plos One
|May 7, 2011
Summary
The second to fourth digit ratio (2D:4D) may indicate prenatal androgen exposure. Alcohol-dependent individuals exhibit lower 2D:4D ratios, suggesting a potential marker for identifying alcohol dependency, especially in males.
Area of Science:
- Endocrinology
- Neuroscience
- Behavioral Genetics
Background:
- The second to fourth digit ratio (2D:4D) is a proposed marker for prenatal androgen exposure.
- Lower 2D:4D ratios are observed in males and linked to traits associated with alcohol dependency vulnerability.
Purpose of the Study:
- To investigate the hypothesis that lower 2D:4D ratios are present in individuals with alcohol dependency.
- To explore the potential of 2D:4D as a trait marker for alcohol dependency.
Main Methods:
- A study comparing 2D:4D ratios in 131 alcohol-dependent patients and 185 healthy controls.
- Analysis included ROC analysis to assess the accuracy of 2D:4D in detecting alcohol dependency.
Main Results:
- Alcohol-dependent patients showed significantly smaller 2D:4D ratios compared to controls.
- Sexual dimorphism in 2D:4D was preserved, but right-left differences were reduced in the patient group.
- The right-hand 2D:4D ratio in males demonstrated the highest accuracy (AUC 0.725) for detecting alcohol dependency.
Conclusions:
- Findings suggest a role for prenatal androgen exposure in alcohol dependency development.
- The 2D:4D ratio, particularly in males, may serve as a useful trait marker for identifying individuals with alcohol dependency.
