摘要:

&NA;The study of discordant monozygotic twins may identify important developmental risk factors for adult psychiatric disorder. Differential experiencein uterois one candidate environmental risk factor that may distinguish monozygotic twins. In this report, we examine whether intra‐pair differences in birth weight predicts discordance for adult psychiatric disorders in 527 female monozygotic twin pairs from a population‐based twin registry. Twins were personally interviewed about their lifetime history of DSM‐III‐R alcoholism, anorexia nervosa, bulimia nervosa, generalized anxiety disorder, major depression, panic disorder, social phobia and simple phobia. Birth weight was estimated from birth certificates, or from retrospective maternal, paternal and self‐reports. Conditional logistic regression is used to characterize the association between intra‐pair differences in birth weight and discordance for psychiatric disorder in monozygotic twins. The twin with the heavier birth weight in discordant pairs is (insignificantly) more likely to have a history of alcoholism or bulimia. The twin with the lighter birth weight in discordant pairs is (insignificantly) more likely to have a history of major depression, simple phobia, panic disorder, anorexia nervosa, social phobia or generalized anxiety disorder. For all psychiatric disorders examined, the lighter (or heavier) co‐twin at birth is not systematically the affected twin within discordant pairs.

ISSN:0955-8829    

出版商:OVID    

年代:2000

数据来源: OVID

摘要:

&NA;Antipsychotic metabolism cosegregates with the polymorphic cytochrome P4502D6 (CYP2D6) hepatic enzyme. Approximately 5‐10% of Caucasians show impaired metabolism associated with nonfunctional alleles. Genotyping determines the number of functional alleles, which is phenotypically not possible. The aim of this study was to investigate associations between CYP2D6 genotype, antipsychotic exposure, and abnormal involuntary movement scale (AIMS) score. Schizophrenic patients (DSM‐IV) were genotyped for CYP2D6*1, *3, and *4 alleles by nested polymerase chain reaction. A complete history, including psychiatric symptoms, medications and AIMS score was obtained. Antipsychotic exposure was recorded in dose years [(chlorpromazine equivalents × years) / 100]. A linear regression model used AIMS scores as the dependent variable. Genotype, gender, antipsychotic exposure, and interactions were independent variables. The results of the 31 patients studied showed: 20 were homozygous for the *1 allele (*1/*1) and 11 were heterozygous for the *1 allele (i.e. *1/*3 or *4). Age, sex, age of onset, treatment duration, antipsychotic exposure, and AIMS scores did not differ between groups. The interaction between dose years and genotype was significant (P< 0.0055), demonstrating that for (*1/*1) patients, the magnitude of antipsychotic exposure had a greater effect on AIMS score (slope = 0.044) compared with (*1/*3 or *4) patients (slope = 0.001). These results suggest patients with a *3 or *4 allele may have a higher risk for developing antipsychotic induced abnormal movements.

ISSN:0955-8829    

出版商:OVID    

年代:2000

数据来源: OVID

摘要:

&NA;Both environmental and genetic factors appear to contribute to the risk for suicide. The serotonergic system has been implicated in depression, impulsivity and suicidality. Tryptophan hydroxylase (TPH) is the rate‐limiting enzyme in the synthesis of serotonin. Suicide has been associated with polymorphisms in intron 7 of the TPH gene. These alleles were studied in samples from 47 deceased Caucasian males as part of the Utah Youth Suicide Study. A 918 base pair fragment spanning the region of interest was amplified. The A218C polymorphism was visualized by restriction fragment length polymorphism (RFLP) and the A779C was sequenced. Neither A218C nor A779C appeared to be associated with suicide in this population. These results did not change when the sample was stratified by age (10‐21 years, 22‐31 years) or when violent suicides were selected. The complexity of the phenotype of suicide may reflect multiple biological and social etiologic factors, and poses a worthy challenge for genetic studies.

ISSN:0955-8829    

出版商:OVID    

年代:2000

数据来源: OVID

摘要:

&NA;Serotonergic neurotransmission has been implicated in suicidal behavior. Polymorphisms in the genes coding for tryptophan hydroxylase, serotonin receptor 2A and serotonin transporter were investigated in a sample of suicide attempters (n= 165) and healthy control subjects (n= 99). No significant differences were found for any of the investigated polymorphisms. Neither did any significant differences emerge in comparison with control subjects when the suicide attempters were grouped into different diagnostic categories: unipolar disorder (n= 45), adjustment disorder (n= 37), substance use disorder (n= 37) and personality disorder, cluster B (n= 36). The results suggest that alleles defined by the investigated polymorphisms do not represent a major determinant in suicide attempt. However, a highly significant (P= 0.001; odds ratio, 1.47; 99% confidence interval, 1.42‐1.53) allelic association between tryptophan hydroxylase and suicide attempt is indicated after pooling our data with literature data. In light of previous data, a possible association between the tryptophan hydroxylase polymorphism and a phenotype that may become differently stratified within differently selected samples of suicide attempters is discussed.

ISSN:0955-8829    

出版商:OVID    

年代:2000

数据来源: OVID

摘要:

&NA;The frequency of three selected mitochondrial DNA variations was compared between cases with schizophrenia and two groups of unrelated controls: screened adults and neonates. The comparisons were conducted separately among Caucasians and African‐Americans. No significant differences were detected, suggesting that the variants may not be associated with schizophrenia. Limitations of the study are discussed.

ISSN:0955-8829    

出版商:OVID    

年代:2000

数据来源: OVID

摘要:

&NA;A number of studies using the repeat expansion detection (RED) technique have suggested an association between unknown large CAG/CTG repeats and schizophrenia. The polymorphic CAG/CTG repeat lociCTG18.1andERDA1have been reported to account for a high proportion (∼ 90%) of the large repeats detected by RED and may therefore be responsible for the cited association. The recently described locusTGC13‐7acontains a highly polymorphic CTA/TAG and CAG/CTG composite repeat, and is thus another authentic candidate. In the present investigation, each locus was analysed for association with schizophrenia in a sample of 206 patients and 219 group‐matched controls. No evidence for association ofCTG18.1, ERDA1and/orTGC13‐7awith schizophrenia was found. The combined data accounted for only 54% of the CAG/CTG arrays of > 40 repeats found in our previous RED analysis.

ISSN:0955-8829    

出版商:OVID    

年代:2000

数据来源: OVID

摘要:

&NA;The noradrenergic system has been implicated in arousal, vigilance, irritability hostility, and memory. This suggests the hypothesis that genetic variants at noradrenergic receptors may be risk factors of these behaviors. To test this hypothesis, the potential association between measures of these traits and genetic variation at the adrenergic2Areceptor gene (ADRA2A), using a common single nucleotide polymorphism (SNP) polymorphism of the promoter region, were examined in two independent sets of subjects: university students (student group), and parents of twins in the Minnesota Twin Study (twin group). In the student group, there was a significant linear association by genotype (11 > 12 > 22) for the total Brown ADD score (BADD), and BADD subscores of memory and irritability, and with the total Buss‐Durkee Hostility Inventory (BDHI) score and BDHI subscores of indirect hostility, irritability, negativity, and verbal aggression. A multiple analysis of variance (MANOVA) of all the BADD and BDHI subscores was significant atP≤ 0.009. For the twin group, the same genotype associations were significant for the Multidimensional Personality Questionnaire (MPQ) impulsivity scores but not for the MPQ aggression or harm avoidance scores. TheADRA2Agene accounted for 1.8‐8.3% of the variance of these scores.

ISSN:0955-8829    

出版商:OVID    

年代:2000

数据来源: OVID

摘要:

&NA;The dopamine D3 receptor gene is of potential interest in the physiopathology of affective disorder because of its expression pattern in brain structures controlling various aspects of behaviour, cognition and emotions. Moreover, it encodes for a receptor protein that is a target for psychotropic drugs, which turn out to be efficient in the treatment of this disorder. Two polymorphisms have been described at this locus (the Bal I and the Msp I Restriction Fragment Length Polymorphisms) that are useful in genetic studies. We therefore researched these polymorphisms in 60 patients suffering from bipolar affective disorder who were compared with 60 healthy volunteers. No statistical difference was observed between the whole patient sample versus the controls. However, one subgroup [homozygous for the (2‐2) Bal I polymorphism] exhibits a characteristic clinical pattern consisting of: manic monopolar form of bipolar disorder, low age of onset and initiation by an acute delusional episode. A gender distribution difference for the Bal I polymorphism (X2= 6.61, degrees of freedom = 1,P= 0.01) was then noted, the bipolar females being preferentially heterozygous, and the males homozygous. These results could involve the dopamine D3 receptor locus as a minor effect gene in the manic depression condition.

ISSN:0955-8829    

出版商:OVID    

年代:2000

数据来源: OVID

摘要:

&NA;Neurotensin (NT) localizes within dopaminergic neurones in the mesocortical, mesolimbic and nigrostriatal systems, and it is now clear that NT can selectively modulate dopaminergic neurotransmission. It has therefore been proposed that altered NT function might contribute to the pathogenesis of neuropsychiatric disorders in which disordered dopaminergic neurotransmission is suspected. We have previously screened the gene encoding NT in a sample of schizophrenic and bipolar subjects, and identified three sequence variants. These have now been tested for association with bipolar disorder using a case‐control sample of unrelated bipolar subjects and matched controls. No evidence for association was found, and our data therefore suggest that sequence variation in this gene does not make an important contribution to susceptibility to bipolar disorder.

ISSN:0955-8829    

出版商:OVID    

年代:2000

数据来源: OVID

ISSN:0955-8829    

出版商:OVID    

年代:2000

数据来源: OVID