We have constructed a linkage map of eight RFLP markers located on chromosome 11 q in the region of the dopamine D2 receptor gene (DRD2) recognized by probe hD2Gl. Abnormalities in dopaminergic neurotransmission mediated by this receptor have been implicated in several psychiatric disorders. The map was generated using six large reference families (from 294 to 419 individuals per locus), which are largely independent of the CEPH families, primarily using the LINKMAP and ILINK programs of the LINKAGE package of Lathrop and Lalouel. The most likely order and recombination frequencies are: cen-DllS146-INT2-D11S36-(DllS84, STMY)-DRD2-D11S29-PBGD-qter 0.001 0.213 0.123 0.001 0.158 0.035 0.093 The relative order of Dl 1S84-STMY, DRD2-D11S29, and D11S146-INT2 could not be resolved reliably. There were no significant sex differences in recombination frequency. We introduce here a version of LINKMAP adapted to run under distributed parallel processing (LINDA-LINKMAP). Using pairwise analyses, we have also placed D11S421 proximal to this group.