ObjectiveIt has been demonstrated that the P300 components, a positive event-related potential, are heritable and are influenced by dopaminergic activity. We tested the genetic effects of the dopaminergic system in P300 components by association study.MethodsIn a sample population consisting of 120 normal young Han-Chinese females, we explored the association between the P300 components, and, the genetic polymorphisms including the dopamine D3 receptor (serine-to-glycine polymorphism in exon I), the dopamine D4 receptor (variable number tandem repeat polymorphism in exon III), and the dopamine transporter (variable number tandem repeat polymorphism in promoter region).ResultsNo associations were demonstrated between the polymorphisms of these three genes and the P300 components.ConclusionsOur negative findings suggest that these genetic polymorphisms do not play a major role in the modulation of P300 event-related potentials.