Since a common variant of the MTHFR gene, T677(Ala), responsible for the thermolabile MTHFR with less than 50% specific MTHFR activity, has been reported, we examined whether the T677 allele is associated with psychiatric disorders in an unrelated Japanese population consisting of 297 schizophrenics, 32 patients with major depression, 40 patients with bipolar disorder, and 419 controls.
In light of other data the variation of TH-K1 and TH-K3 suggests that these alleles may reflect predisposition for a common phenotype with altered vulnerability for psychiatric disorders.
Whether variations in ADCY7 and possible variations in other members of this gene family are underlying other psychiatric disorders remains to be studied.
Catechol-O-methyltransferase (COMT) is one of the major mammalian enzymes involved in the metabolic degradation of catecholamines and is considered a candidate for several psychiatric disorders and symptoms, including the psychopathology associated with the 22q11 microdeletion syndrome.
Our findings indicate that the -141C Del variant in the 5' flanking region of the human dopamine D2 receptor gene is unlikely to play a substantial role in genetic predisposition to major psychiatric disorders in Caucasians.
A recently described functional variant in the DRD2 promoter (-141CIns/Del), which is about 250 kb 5' to the variants studied in psychiatric illness, could conceivably provide an explanation for the positive findings, if it were in linkage disequilibrium with DRD2*A1 in populations similar to those for which an association has been reported.
We have conducted a population-based association study of substance abuse and a microsatellite at the dopamine D5 receptor locus (DRD5) in a sample of European-American males and females with substance dependence (SA) or without any psychiatric disorder.
This finding was inconsistent with previous reports that showed either a high prevalence or absence of BDV p24 RNA in patients with psychiatric disorders.
This finding was inconsistent with previous reports that showed either a high prevalence or absence of BDV p24 RNA in patients with psychiatric disorders.
This expression pattern is consistent with GSCL having either an indirect role in the development of neural crest-derived structures or a direct role in a subset of the phenotype observed in DGS/VCFS, such as learning disorders or psychiatric disease.
This finding was inconsistent with previous reports that showed either a high prevalence or absence of BDV p24 RNA in patients with psychiatric disorders.
Neuroanatomic distribution and pharmacological properties of the serotonin 5-HT7 receptor suggest that it may play a role in psychiatric disorders and in circadian rhythm regulation.
This finding was inconsistent with previous reports that showed either a high prevalence or absence of BDV p24 RNA in patients with psychiatric disorders.
This finding was inconsistent with previous reports that showed either a high prevalence or absence of BDV p24 RNA in patients with psychiatric disorders.
This finding was inconsistent with previous reports that showed either a high prevalence or absence of BDV p24 RNA in patients with psychiatric disorders.
It has been suggested that a common functional genetic polymorphism in the COMT gene, which results in 3 to 4-fold difference in COMT enzyme activity, may contribute to the etiology of mental disorders such as bipolar disorder and alcoholism.
In particular, the impulsive-hyperactive type of ADHD (excluding inattention) ascertained by Diagnostic and Statistical Manual of Mental Disorders (DSM IV) criteria (chi(2) = 8.34, p = 0.004, df = 1), by the Conners Teaching Rating Hyperactivity scale (Pearson chi(2) = 5.32, p = 0.02, df = 1) as well as by the Continuous Performance Test False Alarm scale (chi(2) = 2.78, p = 0.096, df = 1) were associated with the high enzyme activity COMT val allele.
Neurotransmission mediated by DRD2 is known to have a key role in the control of movement and also has been implicated in reward and reinforcement mechanisms and psychiatric disorders.
Forty-seven inpatients affected by bipolar disorder (Diagnostic and Statistical Manual of Mental Disorders IV) were assessed at admission by the Operational Criteria for Psychotic Illness and were typed for DRD2 variants using polymerase chain reaction techniques.
Reports of allelic associations were originally made with alcoholism, but were then extended to other psychiatric disorders; there has been a series of positive reports suggesting an association between DRD2 alleles and substance dependence in European-American (EA) subjects.