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Association between ADORA2A and DRD2 polymorphisms and caffeine-induced anxiety
Emma Childs1, Christa Hohoff, Jürgen Deckert
1Department of Psychiatry, The University of Chicago, Chicago, IL 60657, USA. echilds@yoda.bsd.uchicago.edu
Summary
Caffeine
Area of Science:
- Pharmacogenetics
- Neuroscience
- Human Genetics
Background:
- Caffeine's psychostimulant and anxiogenic effects stem from adenosine receptor antagonism.
- Adenosine and dopamine receptors interact in the brain, suggesting genetic variations may influence caffeine response.
- Individual differences in caffeine sensitivity are partly explained by genetic factors.
Purpose of the Study:
- To investigate the association between self-reported anxiety induced by caffeine and genetic variations in adenosine A(2A) (ADORA2A) and dopamine D(2) (DRD2) receptors.
- To explore potential gene-gene interactions between ADORA2A and DRD2 polymorphisms in relation to caffeine's anxiogenic effects.
Main Methods:
- A double-blind, placebo-controlled study involving 102 healthy individuals with low weekly caffeine consumption.
- Participants ingested varying doses of caffeine (0, 50, 150, 450 mg) across four sessions.
- Subjective anxiety was measured using Visual Analog Scales (VAS) at multiple time points post-ingestion.
Main Results:
- A moderate caffeine dose (150 mg) showed significant associations between induced anxiety (VAS) and specific ADORA2A (rs5751876, rs2298383, rs4822492) and DRD2 (rs1110976) polymorphisms.
- Two-locus interactions between ADORA2A and DRD2 polymorphisms were also linked to caffeine-induced anxiety.
- Higher caffeine doses (450 mg) increased anxiety in most participants, while lower doses did not.
Conclusions:
- Findings support a link between ADORA2A gene variations and self-reported anxiety following moderate caffeine intake.
- Genetic variations in ADORA2A and DRD2 receptors likely contribute to individual responses to caffeine.
- Further research into ADORA2A and DRD2 polymorphisms can elucidate caffeine's complex effects.
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