Association study of schizophrenia spectrum disorders and dopamine D3 receptor gene: is schizoaffective disorder special?

Abstract Alterations in dopamine neurotransmission have been hypothesized to play a role in the etiology of schizophrenia. We considered the dopamine D3 receptor gene on chromosome 3 as a candidate gene for an association analysis. We compared PCR-based genotype markers for healthy controls ( n= 120) and patients ( n= 95) with schizophrenia and schizophrenia spectrum disorders as diagnosed by consensus according to DSM-III-R. Our results possibly indicate an association of schizoaffective disorder with DRD3 homozygosity ( P= 0.056).