Histamine dysregulation was implicated as a rare cause of Tourette syndrome and other tic disorders a decade ago by a landmark genetic study in a high density family pedigree, which implicated a hypomorphic mutation in the histidine decarboxylase (Hdc) gene as a rare but high penetrance genetic cause.
We combined a case-control genetic association analysis and nuclear pedigrees transmission disequilibrium test (TDT) analysis to investigate the association between DRD3 gene rs6280 single nucleotide polymorphisms (SNPs) and TS in a Han Chinese population.
The Bal I and Msp I polymorphisms in the dopamine D3 receptor gene display, linkage disequilibrium with each other but no association with Tourette syndrome.
Controversial results possibly suggesting an association between Tourette's Syndrome (TS) and excess of homozygosity at a Msc I polymorphism in the Dopamine D3 receptor (DRD3) gene have recently been reported.
Although less intensively studied than substance use disorders, the DRD2 gene has been implicated in Tourette's syndrome (TS), post-traumatic stress disorder (PTSD) and certain symptoms associated with affective disorders and schizophrenia.
The objective of this study was to report clinical details and results of genetic testing for mutations in the epsilon-sarcoglycan (SGCE) gene, the Slit and Trk-like 1 (SLITRK1) gene and for linkage to the DYT15, DYT1, and DRD2 gene loci in a family with autosomal dominant myoclonus-dystonia (M-D) and Gilles de la Tourette syndrome (GTS).
Polymorphisms of three different dopaminergic genes, dopamine D2 receptor (DRD2), dopamine beta-hydroxylase (D beta H), and dopamine transporter (DAT1), were examined in Tourette syndrome (TS) probands, their relatives, and controls.
While DRD2 hypermethylation seems to be directly related to the neurobiology of TS that may lead to dopaminergic dysfunction resulting in enhanced thalamo-cortical movement-stimulating activity, DAT hypomethylation might reflect a secondary mechanism in order to compensate for increased dopaminergic signal transduction due to DRD2 hypermethylation.
This rules out causation of Gilles de la Tourette syndrome by mutation in DRD2 in the kindreds studied under the genetic assumptions we employed; use of the map and multipoint linkage analyses also allowed us to exclude a Gilles de la Tourette syndrome susceptibility locus from a larger genetic region.
The dopamine D2 receptor gene (DRD2) appears to be one of these genes since variants at this locus are significantly increased in frequency in TS, ADHD, conduct disorder and drug abuse.
In this study, we used a family-based association approach to investigate the implication of dopamine-related candidate genes, which had been previously reported as possibly associated with TS [genes that encode for the dopamine receptors DRD2, DRD3 and DRD4, the dopamine transporter 1 (SLC6A3) and the monoamine oxidase-A (MAO-A).
Our findings replicate the association of DRD2 and GTS, and are consistent with the proposed connection between the dopamine system and this complex neuropsychiatric disease.
If this allelic system at DRD2 is associated with severity of TS, then among affected family members, those with the A1 allele should have more severe disease than those without it.
In this study, we used a family-based association approach to investigate the implication of dopamine-related candidate genes, which had been previously reported as possibly associated with TS [genes that encode for the dopamine receptors DRD2, DRD3 and DRD4, the dopamine transporter 1 (SLC6A3) and the monoamine oxidase-A (MAO-A).
Polymorphisms of three different dopaminergic genes, dopamine D2 receptor (DRD2), dopamine beta-hydroxylase (D beta H), and dopamine transporter (DAT1), were examined in Tourette syndrome (TS) probands, their relatives, and controls.
In patients suffering from Tourette's disorder (TD) we were unable to detect differences of dopamine transporter densities between psychotropic drug-naïve TD patients and controls.
The purpose of this study was to investigate the role of deep brain stimulation (DBS) of the globus pallidus internus (GPi) in dopamine and dopamine transporter metabolism and to explore the regulatory role of DBS on dopaminergic neurons in Tourette syndrome by constructing an autoimmune model.
A statistical re-evaluation of the DAT1 DdeI polymorphism following population stratification confirmed the association for the TS-total and TS-only groups, but the degree of significance was reduced (P = 0.017 and P = 0.016, respectively).