Cloning of the human dopamine D5 receptor gene and identification of a highly polymorphic microsatellite for the DRD5 locus that shows tight linkage to the chromosome 4p reference marker RAF1P1.

We identified a cosmid clone with exact sequence homology to part of the human dopamine D5 receptor gene (DRD5) after screening a cosmid library with the human DRD1 gene. The dopamine D5 receptor was mapped to chromosome 4p15.1-p15.3 by in situ hybridization and using a somatic cell hybrid panel. We report here the further localization of the DRD5 gene following identification of a highly polymorphic dinucleotide repeat sequence in the cosmid clone. The microsatellite (D5(CT/GT/GA)n) had 12 alleles with a polymorphic information content value of 0.77. Linkage analysis in 39 CEPH pedigrees demonstrated tight linkage to the chromosome 4p reference marker RAF1P1 (Zmaxf 20.66 at theta f 0.05 and ZmaxM 16.57 at theta m 0.07).