To obtain insights regarding DRD1 and post-synaptic glutamatergic genes directly in the human brain, we evaluated genetic associations in various heroin abuse populations and measured expression of the genes within postmortem striatal specimens. The findings reveal that DLG4 and DRD1 are associated with opiate abuse. In addition, there is evidence of a gene-gene interaction between HOMER1 and DRD1 with heroin abuse highlighting a potential disturbance between glutamatergic-DRD1 pathways.
