摘要:

Chromosome 18 is one of the most promising chromosomes in the search for susceptibility genes for bipolar disorder based on results from cytogenetic, linkage, and association studies. Susceptibility loci on chromosome 18p and 18q have been suggested for bipolar affective disorder. We present a review of published studies which suggests that it is presently unclear whether one or more susceptibility loci on chromosome 18 exist, and that their more accurate localization is unknown. The present study investigated 27 DNA markers on chromosome 18 in two Danish families with bipolar affective disorder. We found positive lod scores in the larger family for markers on chromosome 18q12, especially for the affection status model which only includes bipolar patients. The highest lod score found was for marker D18S67, 1.83 at 0.05 recombination fraction.

ISSN:0955-8829    

出版商:OVID    

年代:1997

数据来源: OVID

摘要:

Abnormal catecholamine transmission has been implicated in the pathogenesis of mood disorders. Consequently, alterations in genes that are involved in catecholamine metabolism could be potential candidates for bipolar affective disorder (BPD) vulnerability. One such candidate is catechol-O-methyltransferase (COMT). A functional polymorphism has recently been characterized that is responsible for substantial variability in COMT enzymatic activity. A relatively low activity allele is associated with a methionine residue at amino acid 158 of membrane bound COMT whereas a high activity variant has a valine at this site. We have now screened 63 unrelated patients with BPD for this functional polymorphism. However, no significant association was detected. This suggests that the codon 158COMTpolymorphism is not a susceptibility gene in BPD.

ISSN:0955-8829    

出版商:OVID    

年代:1997

数据来源: OVID

摘要:

We studied the relationship of D2 and D1 receptor gene polymorphisms and alcoholism in male Finnish alcoholics and assessed male controls. Seventy alcoholics entering a detoxification programme and 50 control individuals were recruited. Forty-three per cent of the alcoholic patients, but only 22% of controls, had the D2 receptor geneTaqIA restriction fragment length polymorphism A1 allele. The frequency of the Al allele was significantly higher in alcoholics (p= 0.039). In comparison, no association between alcoholism and the D1 receptor geneEcoRI restriction fragment length polymorphism alleles was found. A logistic regression analysis of the alcoholic population failed to support the idea that the presence of the Al allele would be linked to estimates of alcohol dependence severity rated with the Severity of Alcohol Dependence Questionnaire or the Michigan Alcoholism Screening Test. In conclusion, allelic association between the D2 but not D1 receptor gene and alcoholism in a genetically relatively homogenous population of male Finns was found. The results are in agreement with the view that the D2 receptor locus is involved in genetic susceptibility to alcoholism but does not give support to a special association of severe alcohol dependence and the A1 allele of the D2 receptor gene.

ISSN:0955-8829    

出版商:OVID    

年代:1997

数据来源: OVID

摘要:

In a re-investigation of the NIMH Psychobiology of Depression data, we have studied the question of shifts towards earlier onset together with the question of steadily increasing lifetime risk of major depression in successive birth-cohorts. Using a contingency-table approach, it turned out that inhomogeneities with respect to successive birth-cohorts exclusively showed up in the neighborhood of principally unobservable combinations of the variables under investigation. Standard approaches to testing independence in cross-classified data, such as the quasi-independence model, yielded highly significant results. Through the definition of a log-linear model with weights which replaces the 'discrete' truncation of the quasi-independence approach by a 'smoothed' truncation, it was possible to fully explain the observed age-of-onset shifts, thus supporting the hypothesis that age-of-onset and birth-cohort are independent. With respect to the question of generational changes in the lifetime risk of depression this independence implied that such changes should occur at equal rates across all ages of onset. The analysis yielded significantly larger cohort sizes for the two youngest birth-cohorts, a fact which might be interpreted as an indication of increasing environmental impacts on the genetically predisposed vulnerability during recent years. However, our cross-sectional survey data were, by design, not an optimal basis for a reliable assessment of changes in the lifetime risk of depression, because the risk estimate derived from affected-only survey data correponds to the probability that a depressive belongs to a certain birth-cohort and is only loosely related to the lifetime risk of this cohort (which is the probability that a person belonging to a certain birth-cohort develops depression). We therefore conclude, firstly, that method effects are likely to explain a major portion of secular trends thus far reported in the literature, and, secondly, that there appears to be no clear necessity to include changing environmental effects into quantitative genetic modelling.

ISSN:0955-8829    

出版商:OVID    

年代:1997

数据来源: OVID

摘要:

Recent studies have reported an association between a 102T/C polymorphism of serotonin receptor type 2A gene (5-HT24) and schizophrenia. In addition, an association was detected between a 102T/C polymorphism of the 5-HT24receptor gene and drug response to clozapine in the treatment of schizophrenic patients. These studies suggest an important role of the 5-HT24gene in schizophrenia. To study the possible involvement of the 5-HT24gene in the pathogenesis of schizophrenia, a case-control association study was carried out in a Chinese population from Taiwan. No significant differences of genotype distributions, allele frequencies and homozygosity were detected between schizophrenic patients (n= 177) and non-psychiatric controls (n= 98). When subjects were divided into subgroups according to sex, still no differences of allele frequencies or genotype distributions were noted between patients and controls. Our data do not support an allelic association between the 102T/C polymorphism of the 5-HT24, receptor gene and schizophrenia in Chinese population.

ISSN:0955-8829    

出版商:OVID    

年代:1997

数据来源: OVID

ISSN:0955-8829    

出版商:OVID    

年代:1997

数据来源: OVID

摘要:

Prader-Willi syndrome is caused by a deletion of 15q11–13 or maternal disomy of chromosome 15. A female patient with Prader-Willi syndrome, who was 19 years of age at the first onset of her recurrent brief episodes, is described. The episodes showed a near-monthly rhythm and were followed by a spontaneous remission in 7–18 days. The symptoms during the episodes were anorexia, insomnia, guilt feelings, ideas of being doomed, ostracized and persecuted, and stupor alternating with agitation.

ISSN:0955-8829    

出版商:OVID    

年代:1997

数据来源: OVID

摘要:

To probe the hypothesis of a role for a functionally relevant 44 hp insertion/deletion of the serotonin transporter promoter in the aetiopathogenesis of panic disorder, we determined the allele frequency of the variant in two samples (combinedn= 158) of panic disorder patients (DSMIII-R) and compared it with its allele frequency in two ethnically matched control samples (combinedn= 169). The fact that no difference could be observed (χ2analysis) argues against a major role for this serotonin transporter promoter polymorphism in the aetiopathogenesis of panic disorder.

ISSN:0955-8829    

出版商:OVID    

年代:1997

数据来源: OVID

摘要:

Recent reports on susceptibility loci for manic depression have sparked lively debate. The pros and cons of these findings are discussed from a methodological vantage point, with implications for linkage studies generally.

ISSN:0955-8829    

出版商:OVID    

年代:1997

数据来源: OVID