Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0036341 (schizophrenia)
 60,220 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Serotonin receptor 5HTR2A gene polymorphism was reported to be associated with psychiatric disorders, in particular schizophrenia, in numerous studies. This study aimed to analyze a possible association between 5HTR2A gene polymorphism and clinical and pathogenetic characteristics in schizophrenia and schizophrenia spectrum disorders. We studied 209 individuals with schizophrenia and related disorders (107 male and 102 female, mean age 34.7 +/- 17.2 years) and 116 healthy controls (44 males, 72 females, mean age = 33.6 +/- 14.4 years). Diagnoses were made according diagnostic criteria of ICD-10. Positive and Negative Symptoms Scale (PANSS) assessed clinical symptoms. Significant difference (p < 0.01) was found for 5HTR2A genotype distribution between affected and control groups. The frequencies of genotypes A1A1, A1A2 and A2A2 for schizophrenia were 13.3%, 44.0% and 42.7%, respectively, versus 33%, 47% and 27% in controls. These results support the evidence for association between 5HTR2A A2A2 genotype and schizophrenia. Schizophrenics with A2A2 genotype were characterized by significantly higher mean values of the PANSS negative symptoms subscale than those with A1A1 genotype (22.6 vs 17.8; p < 0.05) and, consequently, by majority of deficit patients and patients with more severe forms of schizophrenia. Patients with A1A1 genotype were younger compare to those with A2A2 genotypes and had the least familial factors (35.7% vs 46.1%). In agreement with the results obtained in the study the 5HTR2A gene polymorphism appears to be considered as additional diagnostic or prognostic trait in the medical genetic studies of schizophrenia.
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PMID:[Serotonin receptor gene allele polymorphism (5HTR2A) and clinical pathogenetic characteristics in patients with schizophrenia and schizophrenia spectrum disorders]. 1070 89

Serotonin receptor genes have always been considered excellent candidate genes in the aetiology of neurogenetic diseases. In this study, we assessed sequence variations of the HTR3A gene. For this purpose, we established exon-specific primers and analysed DNA samples from 165 unrelated individuals including 70 schizophrenic patients, 48 patients with bipolar affective disorder and 47 healthy control persons using polymerase chain reaction/single-strand conformational polymorphism analysis. We discovered six sequence variants, five of which represent polymorphisms. These polymorphisms could not be associated with schizophrenia and bipolar affective disorder (P = 0.055-1). We also detected a missense mutation in exon 9 in a schizophrenic patient at a conserved position (Pro391Arg). To determine the incidence of this substitution an extended set of 358 schizophrenic patients and 155 control individuals was investigated. The Pro391Arg mutation was not detected in these schizophrenic patients and controls screened. However, a second missense mutation (Arg344His) was detected in one schizophrenic patient, but not in any of the controls. These results suggest that the observed mutations in HTR3A are rare and therefore do not play a major role in the aetiology of the disorder. Further studies are needed to support the hypothesis that HTR3A may contribute to the schizophrenia in these patients.
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PMID:Serotonin receptor gene HTR3A variants in schizophrenic and bipolar affective patients. 1120 27

Tardive dyskinesia (TD) is a long-term adverse effect of antipsychotic drugs that are dopamine D2 receptor blockers.(1) Serotonin receptor antagonism has been proposed as a common mechanism contributing to the low extrapyramidal effects profile of atypical antipsychotic drugs.(2) We examined the association of three polymorphisms in the 5-HT2A receptor gene (HTR2A) with TD susceptibility--T102C(3) and his452tyr(4) in the coding region and A-1438G(5) in the promoter--in matched schizophrenia patients with (n = 59, SCZ-TD-Y) and without TD (n = 62, SCZ-TD-N) and normal control subjects (n = 96). The T102C and the A-1438G polymorphisms are in complete linkage disequilibrium but not his452tyr. There was a significant excess of 102C and -1438G alleles (62.7%) in the SCZ-TD-Y patients compared to SCZ-TD-N patients (41.1%) and controls (45.9%; chi(2) = 12.8, df = 2, P = 0.002; SCZ-TD-Y vs SCZ-TD-N, chi(2) = 11.4, df = 1, P = 0.0008, OR 2.41, 95% CI 1.43-3.99) and of 102CC and -1438GG genotypes (SCZ-TD-Y 42.4%, SCZ-TD-N, 16.1%, controls 20.8%, chi(2) = 13.3, df = 4, P = 0.01). The 102CC and the -1438GG genotypes were associated with significantly higher AIMS trunk dyskinesia scores (F = 3.9; df = 2, 116; P = 0.02) and more incapacitation (F = 5.0; df = 2, 115; P = 0.006). The his452tyr polymorphism showed no association with TD. These findings suggest that the 5-HT2A receptor gene is significantly associated with susceptibility to TD in patients with chronic schizophrenia. Previously reported association of the T102C and A-1438G polymorphisms with schizophrenia(6) may reflect association of a sub-group of patients with a susceptibility to abnormal involuntary movements related to antipsychotic drug exposure.
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PMID:Association between the serotonin 2A receptor gene and tardive dyskinesia in chronic schizophrenia. 1184 Mar 6

Serotonin receptor (5HTR2A) gene polymorphism has been reported to be associated with clinical phenotypes in schizophrenia. The current study attempted to investigate a relationship between 5HTR2A 102T/C polymorphism and personality traits as well as clinical symptoms in patients with ICD-10 diagnoses of schizophrenia and affective disorders. 5HTR2A genotyping, clinical and psychological assessment were administered to 375 patients, 104 first-degree healthy relatives of the patients and 157 controls. In the patients an association was observed between the 2/2 5HTR2A genotype and scores on the Hypochondriasis scale (MMPI) (ANOVA, F = 4.56; P = 0.011) and trait anxiety (F = 4.21; P = 0.002). A significant difference between 1/1 and 2/2 genotypes has been also found for Neuroticism scores (EPI) (t = 2.18; P = 0.0031). No significant differences by 5HTR2A genotype were observed in either the control or first-degree relatives group for all scales studied. Positive, negative and psychopathological symptoms emerged higher in the 2/2 genotype patients compared to other genotype carriers. Therefore, the 2/2 genotype may contribute to produce the phenotype, with specific clinical and pathological features in common, regardless of nosologic heterogeneity of psychoses.
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PMID:5HTR2A gene polymorphism and personality traits in patients with major psychoses. 1191 89

With the use of chlorpromazine and other traditional antipsychotics for psychosis, it was soon discovered that the antipsychotic efficacy of this class of medications was closely associated with their ability to block dopamine D(2) receptors in the brain. This prompted the hypothesis that the etiology of schizophrenia and other psychotic illnesses might be caused by a dysregulation of dopamine. This hypothesis, that the dopamine system explains schizophrenia symptoms, however, is far from complete and the treatment with conventional antipsychotic medications is far from ideal. There has been a great deal of speculation regarding the role of serotonin receptor antagonism in regards to antipsychotic effects. The second generation antipsychotics (SGAs), clozapine, risperidone, olanzapine, quetiapine and ziprasidone all have relatively high serotonin to dopamine binding ratios. Serotonin receptor binding may be important to these drugs' actions, possibly by stimulating dopamine activity in mesocortical pathways. Yet, while the mechanism of action of SGAs as a group remain unsolved, it is important to note that the SGAs offer many clinical benefits to treatment as compared to traditional antipsychotics and are quickly emerging as first-line therapy for schizophrenia. In addition to lower rates of EPS and tardive dyskinesia, other benefits to treatment with this class of antipsychotics include better treatment of negative symptoms, better compliance, possible benefits for cognitive impairments, lower rates of relapse and rehospitalization, and more cost-effective therapy. Within the class of SGAs, however, differences exist both in efficacy and side effects and these will be described. Optimization of treatment and understanding the exact mechanism of action of current antipsychotic medications will help pave the way for new drug targets in the future.
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PMID:Current status of antipsychotic treatment. 1276 30

Serotonin receptor type 2 (5-HTR2A) polymorphism was consistently reported to be related to schizophrenia and some clinical presentations of the disease. The present study aimed at searching for association between 5-HTR2A polymorphism and schizotypic personality traits being considered as recognized phenotype predisposing to schizophrenia. Relationship between these features measured by SPQ-74 and two 5-HTR2A polymorphic loci has been studied in mentally healthy community sample (n = 64). Significant difference was found between AG and GG genotype carriers on No-close-friends scale (t = 2.3; p = 0.03), with GG scoring higher on this item. Also, a trend towards higher scores on this scale (p = 0.08) was observed in women, but not in men, with A2A2 genotype. To a certain extent, the results confirm a hypothesis articulated in the study of G-allele and A2-allele relation to interpersonal relationship factor of SPQ-74.
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PMID:[Polymorphism of serotonin receptor gene 5-HTR2A and schizotypic traits in mentally healthy subjects]. 1468 67

Clozapine is an antipsychotic known for its superior efficacy in treating drug-resistant Schizophrenia. However, Clozapine induces various side effects such as hyperglycemia, agranulocytosis, weight gain etc. The mechanisms of these Clozapine-induced side effects have remained largely elusive though an important role is ascribed to 5-HT2A (Serotonin receptor subtype-2A). In this pilot study, we report for the first time that the 5-HT2A 'global' knockout mice (Htr2a-/-) are resistant to the Clozapine-induced hyperglycemia. Importantly though, the Htr2a-/- mice exhibit near normal basal glucose metabolism in the glucose tolerance tests. Collectively, the Htr2a-/- mice provide an important tool to study the Clozapine-induced hyperglycemia.
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PMID:5-HT2A deletion protects against Clozapine-induced hyperglycemia. 3060 Jan 45