Dopamine is an endogenous catecholamine that influences many cellular activities, including behavior, hormone synthesis and release, blood pressure and intracellular ion transport.

DRD1 gene encodes the D₁ subtype of the dopamine receptor. The D₁ subtype is the most abundant dopamine receptor in the central nervous system. This G-protein coupled receptor stimulates adenylyl cyclase and activates cyclic AMP-dependent protein kinases. D₁ receptors regulate neuronal growth and development, mediate some behavioral responses, and modulate dopamine receptor D₂-mediated events. Alternate transcription initiation sites result in two transcript variants of this gene.