A mammalian D₂ dopamine receptor gene has been cloned. Thus, DNA sequences encoding all or a part of the dopamine receptor are provided, as well as the corresponding polypeptide sequences and methods for producing the same both synthetically and via expression of a corresponding sequence from a host transformed with a suitable vector carrying the corresponding DNA sequence. The various structural information provided by this invention enables the preparation of labeled or unlabeled immunospecific species, particularly antibodies, as well as nucleic acid probes labeled in conventional fashion. Pharmaceutical compositions and methods of using various products of this invention are also provided.