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Objective: Dopaminergic neurotransmission is implicated in the executive control of cognition and behavior (Braver & Cohen, 2000). Presence or absence of particular dopamine gene alleles relates to executive control performance (Casey, 2002; Roesch-Ely, 2005) and to attention problems and ADHD (Durston, 2005; Schmidt, 2001). The present study examined the relation between dopamine genotype and executive control in normally-developing preschool children. Participants and Methods: The sample included 133 children (66 girls; mean age 4 years, range 2;2-6 years). Children completed a battery of executive control tasks, and were genotyped for 4 dopamine genes: the dopamine receptors DRD2 and DRD4, the dopamine transporter DAT, and the enzyme COMT. Based on a literature review, for each gene, children were classified as carrying the high- or low-risk allele, and a risk score was constructed by summing the number of high-risk alleles (range 0-4). In Mplus, structure equation modeling was used to examine the relation between the genetic risk score and a latent factor representing the executive control battery, controlling for age. Results: The SEM model evidenced good fit to the data (chisquare(43)=43.15, p=.46). Age had a strong positive relationship with executive control, and higher risk scores for dopamine genotype were associated with lower executive control performance (standardized regression coefficients=.76 and -.10, respectively). Conclusions: Dopamine genotype is correlated with executive control performance, perhaps reflecting differences in dopamine availability and efficiency of neurotransmission related to different dopamine alleles. Given that executive control problems are implicated in ADHD (Nigg, 2005), these findings may shed light on how genetic risk contributes to behavioral problems.