Here we compare gene expression levels for 17 genes [including all 11 dopamine receptor interacting proteins, all 5 dopamine receptors (DRD1-DRD5) and DARPP-32] by real-time polymerase chain reaction, using prefrontal cortex post mortem brain samples from 33 schizophrenic, 32 bipolar disorder and 34 control subjects.
A significant increase in the frequency of the 148 bp allele of DRD5 (P = 0.024) and the 244 bp allele of D4S615 (P = 0.001) was found in patients with schizophrenia (n = 158 DRD5; n = 133 D4S615), compared with patients with bipolar disorder (n = 270 DRD5; n = 107 D4S615), or controls without psychiatric illness (n = 437 DRD5; n = 309 D4S615).
A significant increase in the frequency of the 148 bp allele of DRD5 (P = 0.024) and the 244 bp allele of D4S615 (P = 0.001) was found in patients with schizophrenia (n = 158 DRD5; n = 133 D4S615), compared with patients with bipolar disorder (n = 270 DRD5; n = 107 D4S615), or controls without psychiatric illness (n = 437 DRD5; n = 309 D4S615).
Family-based association studies of bipolar disorder with candidate genes involved in dopamine neurotransmission: DBH, DAT1, COMT, DRD2, DRD3 and DRD5.
These studies provided no further evidence supporting the possibility that mutations in DRD5 give rise to the linkage findings or are acting as susceptibility loci in schizophrenia or bipolar disorder.
Linkage analyses using 16 DNA markers covering more than 50 cM from chromosome 4pter-4p12, including candidate genes encoding the dopamine D5 receptor and an adrenergic receptor (2C), were performed in two Danish families with bipolar affective disorder.
Linkage analyses using 16 DNA markers covering more than 50 cM from chromosome 4pter-4p12, including candidate genes encoding the dopamine D5 receptor and an adrenergic receptor (2C), were performed in two Danish families with bipolar affective disorder.