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DRD2 Polymorphism (drd2 + polymorphism)

Distribution by Scientific Domains

Life Sciences	50%

Selected Abstracts

Dopamine gene predicts the brain's response to dopaminergic drug

EUROPEAN JOURNAL OF NEUROSCIENCE, Issue 12 2007
Michael X Cohen
Abstract Dopamine is critical for reward-based decision making, yet dopaminergic drugs can have opposite effects in different individuals. This apparent discrepancy can be accounted for by hypothesizing an ,inverted-U' relationship, whereby the effect of dopamine agents depends on baseline dopamine system functioning. Here, we used functional MRI to test the hypothesis that genetic variation in the expression of dopamine D2 receptors in the human brain predicts opposing dopaminergic drug effects during reversal learning. We scanned 22 subjects while they engaged in a feedback-based reversal learning task. Ten subjects had an allele on the Taq1A DRD2 gene, which is associated with reduced dopamine receptor concentration and decreased neural responses to rewards (A1+ subjects). Subjects were scanned twice, once on placebo and once on cabergoline, a D2 receptor agonist. Consistent with an inverted-U relationship between the DRD2 polymorphism and drug effects, cabergoline increased neural reward responses in the medial orbitofrontal cortex, cingulate cortex and striatum for A1+ subjects but decreased reward responses in these regions for A1, subjects. In contrast, cabergoline decreased task performance and fronto-striatal connectivity in A1+ subjects but had the opposite effect in A1, subjects. Further, the drug effect on functional connectivity predicted the drug effect on feedback-guided learning. Thus, individual variability in how dopaminergic drugs affect the brain reflects genetic disposition. These findings may help to explain the link between genetic disposition and risk for addictive disorders. [source]

Dopamine Receptor D2 Polymorphism Moderates the Effect of Parental Education on Adolescents' School Performance

MIND, BRAIN, AND EDUCATION, Issue 2 2008
Liisa Keltikangas-Järvinen
ABSTRACT, High parental socioeconomic status is known to have a positive effect on students' academic achievement. We examined whether variation in the dopamine receptor gene (DRD2 polymorphism, rs 1800497) modifies the association between parental educational level and school performance in adolescence. The participants were a randomly selected subsample of individuals participating in the Cardiovascular Risk in Young Finns study (921 girls and 742 boys) aged 12,15 years at the time school performance was assessed. The genotyping was performed using TaqMan 5,'-nuclease assay. A significant interaction was found between childhood parental educational level and students' DRD2 polymorphism on academic achievement after adjustment for age, gender, household income, parental occupation, maternal nurturance, hyperactivity, and sociability. Parental educational level was significantly positively associated with school achievement in the A2/A2 (n = 1,061) and the A1/A2 (n = 529) genotype groups, but was negative and statistically insignificant in participants carrying the A1/A1 (n = 73) genotype. It is concluded that the extent to which parental education status affects an individual's academic achievement may be dependent on the individual's genetic constitution. The findings may increase an acceptance of genetic influence in education, and, consequently, may increase accurateness of educational interventions. [source]

GENETIC STUDY: Interaction of SLC6A4 and DRD2 polymorphisms is associated with a history of delirium tremens

ADDICTION BIOLOGY, Issue 1 2010
Victor M. Karpyak
ABSTRACT Several genetic polymorphisms have been reported to be associated with alcohol withdrawal seizures (AWS) and delirium tremens (DT). To replicate and further explore these findings, we investigated the effects of 12 previously reported candidate genetic variations in two groups of alcohol-dependent European Americans with a history of withdrawal, which differed according to the presence (n = 112) or absence (n = 92) of AWS and/or DT. Associations of AWS and/or DT with the genomic and clinical characteristics and gene,gene interaction effects were investigated using logistic regression models. None of the polymorphisms were significantly associated with AWS/DT after correction for multiple testing. However, we found a significant interaction effect of the SLC6A4 promoter polymorphism (5-HTTLPR) and DRD2 exon 8 single nucleotide polymorphism rs6276 on AWS and/or DT history (P = 0.009), which became more significant after adjustment for lifetime maximum number of drinks consumed per 24 hours (P < 0.001). Subsequent analysis revealed an even stronger association of the SLC6A4,DRD2 interaction with DT (P < 0.0001), which remained significant after Bonferroni correction. Results reveal decreased likelihood of DT in alcoholics that carry the DRD2 rs6276 G allele and SLC6A4 LL genotype. This study provides the first evidence to implicate the interaction between serotonin and dopamine neurotransmission in the etiology of DT. Replication is necessary to verify this potentially important finding. [source]