The human dopamine D₂ receptor gene is located on Chromosome 11 at q22-q23 and identifies a TaqI RFLP

Human dopaminergic neurons are involved in the control of hormone secretion, voluntary movement, and emotional behavior. Mediating these effects are the dopamine D₁ and D₂ receptors. These macromolecules belong to a large family of related sequences known as the G protein-coupled receptors. The D₂ receptors have been of special interest because they bind, with high affinity and specificity, many of the commonly prescribed antipsychotic drugs. We previously isolated a full-length cDNA clone of the rat D₂ receptor. When a chromosome mapping panel was probed with the rat D₂ receptor cDNA a 15-kb EcoRI restriction fragment was identified and localized to human chromosome 11. The rat cDNA was also used to clone a human genomic fragment, λhD2G1, which contains the last coding exon of the D₂ receptor gene (DRD2) and 16.5 kb of 3' flanking sequence. Hybridization of λhD2G1 to a chromosome 11 regional mapping panel localized DRD2 to 11q. In situ hybridization of λhD2G1 to metaphase chromosomes refined this asignment to the q22-q23 junction of chromosome 11. A search for RFLPs associated with D2DR identified a frequent two-allele TaqI RFLP.