摘要:

Anorexia nervosa is a severe disorder which seems likely to have a multifactorial aetiology. However, several studies have stressed that genetic factors play a significant role. Epidemiological studies have shown that the lifetime risk for first-degree relatives of a patient with an eating disorder is 6% compared to 1% among relatives of controls, and a twin study performed on 34 pairs of twins has shown a higher concordance rate in monozygotic twins (55%) compared to dizygotic twins (7%). The vulnerability component of anorexia nervosa that can be attributed to genetic influences has been estimated from twin studies to be around 70%. Despite this, few genetic studies have been performed testing the role of candidate genes which code for proteins potentially implicated in the aetiopathogenesis of the disorder. In this review, genes encoding components of the dopamine, serotonin, opiate, and noradrenaline systems are assessed for their role in anorexia nervosa. Attention is paid to psychological dimensions, clinical symptoms, co-morbidity frequency, pharmacological data, and biological measures that characterize anorexia nervosa.

ISSN:0955-8829    

出版商:OVID    

年代:1998

数据来源: OVID

摘要:

Recently, an association has been reported between schizophrenia and a rare allele containing 10-repeats (A10) of a polymorphic tetranucleotide motif in the first intron of the tyrosine hydroxylase (TH) gene. The present association analysis tested the hypothesis that the A10candidate allele confers vulnerability to alcohol-withdrawal delirium with visual hallucinations. The genotype of the TH tetranucleotide polymorphism was assessed in 204 German controls and 311 German alcohol-dependent subjects, including 63 alcoholics with a history of visual hallucinations during withdrawal delirium. The frequency of the A10allele was significantly increased in the alcoholics with withdrawal delirium (3.2%) compared with that in the controls (0.5%; Fisher's exact test:P= 0.03, two-tailed; OR(A10+) = 6.85, 95% confidence interval: 1.52–30.79). The possible allelic association suggests that allelic variation at the TH locus mediates vulnerability to alcohol-withdrawal delirium in a small proportion of alcohol-dependent subjects.

ISSN:0955-8829    

出版商:OVID    

年代:1998

数据来源: OVID

摘要:

Two parts of the dopamine β-hydroxylase (DBH) gene, one a 7.5-kb single copy fragment (F1) spanning the 5‘-flanking region to exon 3 and the second a 9.0-kb single copy fragment (F2) spanning exon 3 to exon 7, were amplified by a long PCR procedure in 161 unrelated patients with schizophrenia and 67 unrelated control subjects. The PCR products were completely digested with the restriction enzymeTaql.These subjects were classified into genetic subgroups according to theTaqlrestriction fragment length polymorphisms (RFLPs) for the human DBH gene, and the association of theTaqlRFLPs with biochemical alterations of the catecholamine pathway in schizophrenia was then examined. The frequencies of the twoTaqlpolymorphic sites did not show significant differences between the patients and control subjects, but theTaqlRFLPs were found to be associated with biochemical alterations of the catecholamine pathway in schizophrenia.

ISSN:0955-8829    

出版商:OVID    

年代:1998

数据来源: OVID

摘要:

Debrisoquine 4-hydroxylase (CYP2D6) is a cytochrome P450 enzyme involved in the metabolism of most neuroleptics, which are the drugs of choice for the treatment of psychotic symptoms. CYP2D6 in the brain was suggested to be functionally similar to the dopamine transporter, thus possibly influencing a neurotransmitter system involved in schizophrenia. Swedish schizophrenic patients (n= 124) and control individuals (n= 85) were investigated for two CYP2D6 polymorphisms, responsible for approximately 90% of mutations leading to poor debrisoquine metabolism. No significant CYP2D6 allele or genotype difference was found between schizophrenic patients and control individuals. Taken together with previous results, no major effect appears to be caused by the CYP2D6 gene on schizophrenia.

ISSN:0955-8829    

出版商:OVID    

年代:1998

数据来源: OVID

摘要:

A number of studies have reported an association between large CAG/CTG repeats and both schizophrenia and bipolar disorder. Recently, we reported an inverse correlation between CAG/CTG repeat size and age in a health-selected population, raising the possibility that selection of control groups for physical health was a confounding factor in our previous association studies. We investigated this by health-selection of patients with schizophrenia and bipolar disorder. The maximum CAG/CTG repeat size remained significantly larger in probands with functional psychosis compared with control individuals, and in probands with a diagnosis of schizophrenia compared with control individuals. The number of probands in the healthy bipolar group was small, and although on average this group also had longer CAG/CTG repeats than control individuals, this failed to reach statistical significance. Our findings do not support the notion that the original results with psychosis as a whole, and schizophrenia specifically, are attributable to a stratification effect consequent on health selection. Nevertheless, we are unable formally to reject the hypothesis that the previously observed difference between bipolar probands and control individuals is the result of this phenomenon.

ISSN:0955-8829    

出版商:OVID    

年代:1998

数据来源: OVID

摘要:

The brain-rich 14–3-3 protein regulates synthesis and excretion of bioamine by activating tyrosine and tryptophan hydroxylases, and by exocytosis of catecholamines and serotonin. In humans, at least eight subunits of the 14–3-3 protein family have been isolated. The 14–3-3 η chain gene is located at 22q12.1 to q13.1, one of the chromosome regions identified as possibly linked to schizophrenia. We systematically searched for nucleotide variants in the coding region, 5′ and 3′ untranslated region, and in the exon-intron boundaries of the genomic 14–3-3 η gene in 24 schizophrenics and 24 controls. Two polymorphic sites were found: one in the 5′ untranslated region and one in the 3′ untranslated region. However, no variants predicting amino-acid alterations were observed. Similar allelic and genotypic distributions for both polymorphisms were found in 308 schizophrenics and 135 controls.

ISSN:0955-8829    

出版商:OVID    

年代:1998

数据来源: OVID

ISSN:0955-8829    

出版商:OVID    

年代:1998

数据来源: OVID