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

The hypothesis that at least a subgroup of familial cases of schizophrenia could be due to a genetic defect on the X chromosome is supported by the observation of an excess of X-chromosome aneuploidies (XXX and XXY) among populations of patients with psychosis. The distal long arm, Xq27-q28, is a candidate region where linkage has been claimed to manic-depressive disorder and a fragile site has been associated with schizophrenia spectrum disorders. The present study excluded linkage to a large part of this region using four polymorphic probes and multipoint lod-score analysis in 10 families with multiple members with schizophrenia.
 ...
PMID:No genetic linkage detected for schizophrenia to Xq27-q28. 167 99

Schizoaffective illness has either been linked to schizophrenia and to affective disorders, or it has been considered to be as separate entity. Family and linkage studies can provide data regarding genetic factors in the aetiology of schizoaffective illness. Morbidity risks for affective illnesses and schizophrenia were estimated in the first-degree relatives of schizoaffective probands as compared to matched controls (bipolars, unipolars and schizophrenics). Linkage studies with X-chromosome markers (protanopia and deuteranopia) were also performed in informative families. Our genetic results indicate that schizoaffective illness is a heterogeneous entity. This syndrome appears to be primarily related to the affective disorders, but there may be a subgroup linked to the schizophrenic spectrum disorders. Our studies also indicate that some schizoaffective syndromes may be transmitted through the X-chromosome, a pattern previously demonstrated in some families with bipolar manic-depressive illness.
 ...
PMID:Relationship between schizoaffective illness and affective disorders or schizophrenia. Morbidity risk and genetic transmission. 645 Jul 88

Clinico-anthropometric investigation of 300 patients suffering from paranoid schizophrenia has been carried out. The results of a correlation analysis of anthropometric characteristics and of an analysis of manifestation age of schizophrenia showed that the closest connection of the traits studied exists in the group of females with the attack-like paranoid schizophrenia. The data are interpreted as the confirmation of the X-chromosome effect in schizophrenia and of interaction between the locus system of schizophrenia and the morphotype system.
 ...
PMID:[Anthropometric characteristics of paranoid schizophrenics as a conjectured marker of the age of manifestation of the process]. 695 22

A sex chromosome locus for psychosis has been considered on the basis of some sex differences in genetic risk and expression of illness, and an association with X-chromosome anomalies. Previous molecular genetic studies produced weak evidence for linkage of schizophrenia to the proximal short arm of the X-chromosome, while some other regions were not ruled out. Here we report an attempt to expand the Xp findings in: (i) a multicenter collaboration focusing on 92 families with a maternal pattern of inheritance (Study I), and (ii) an independent sample of 34 families unselected for parental mode of transmission (Study II). In the multicenter study, a parametric analysis resulted in positive lod scores (highest of 1.97 for dominant and 1.19 for recessive inheritance at a theta of 0.20) for locus DXS7, with scores below 0.50 for other markers in this region (MAOB, DXS228, and ARAF1). Significant allele sharing among affected sibling pairs was present at DXS7. In the second study, positive lod scores were observed at MAOB (highest of 2.16 at a theta of 0.05 for dominant and 1.64 at a theta of 0.00 for recessive models) and ALAS2 (the highest of 1.36 at a theta of 0.05 for a recessive model), with significant allele sharing (P = 0.003 and 0.01, respectively) at these two loci. These five markers are mapped within a small region of Xp11. Thus, although substantial regions of the X-chromosome have been investigated without evidence for linkage being found, a locus predisposing to schizophrenia in the proximal short arm of the X-chromosome is not excluded.
 ...
PMID:A linkage study of schizophrenia to markers within Xp11 near the MAOB gene. 921 75

30 patients (4-22 years old) and their 12 mothers were examined by means of method of electroencephalography (EEG). Healthy individuals of corresponding age were included in the control group. EEG changes of the same type were observed in all the patients with syndrome of fragile X-chromosome: reduction of occipital alpha-rhythm, prevalence of theta-rhythm in central-parietal and central frontal regions as well as epileptoid activity in parietal and central-parietal cortical regions. These peculiarities could be considered as the markers in syndrome's diagnostics. EEG of mothers (heterozygous carriers of mutant gene) were characterised by considerable variations: increase of rolandic rhythm's presentation in central cortical zones, accumulation of hypersynchronous EEG, increase of rhythmical theta-activity, etc. EEG of mother with shift-like schizophrenia resembled one of proband in one case.
 ...
PMID:[Brain bioelectrical activity in patients with the fragile X-chromosome syndrome and in their mothers]. 934 80

Researchers presented results of ongoing research to the X-chromosome workshop of the Fifth World Congress on Psychiatric Genetics, covering a wide range of disorders: X-linked infantile spasms; a complex phenotype associated with deletions of Xp11; male homosexuality; degree of handedness; bipolar affective disorder; schizophrenia; childhood onset psychosis; and autism. This report summarizes the presentations, as well as reviewing previous studies. The focus of this report is on linkage findings for schizophrenia and bipolar disorder from a number of groups. For schizophrenia, low positive lod scores were obtained for markers DXS991 and DXS993 from two studies, although the sharing of alleles was greatest from brother-brother pairs in one study, and sister-sister in the other. Data from the Irish schizophrenia study was also submitted, with no strong evidence for linkage on the X chromosome. For bipolar disease, following the report of a Finnish family linked to Xq24-q27, the Columbia group reported some positive results for this region from 57 families, however, another group found no evidence for linkage to this region. Of interest, is the clustering of low positive linkage results that point to regions for possible further study.
 ...
PMID:X-chromosome workshop. 968 35

Both Turner syndrome and schizophrenia are relatively infrequent conditions. Consequently, individuals having both illnesses are rare. Previous reviews of sex chromosome abnormalities in schizophrenia have focused primarily on the presence of supernumerary X-chromosomes. After identifying two female patients with schizophrenia and Turner syndrome, we reevaluated the available literature that survey female schizophrenics for the presence of chromosomal abnormalities. Eleven patients with Turner syndrome were identified among 6,483 females with schizophrenia in non-case-report studies. These survey results indicate that Turner syndrome occurs approximately three-fold more frequently in schizophrenic females than in the general female population (P < 0.02). Including 6 other case reports and our 2 cases, a total of 19 females with both schizophrenia and Turner syndrome were reported. Interestingly, whereas most Turner syndrome patients have the 45,X karyotype, the majority (18/19) of women with both illnesses have a mosaic karyotype (P < 0.0002). Given the potential role of genes on the X-chromosome in the pathogenesis of schizophrenia, the study of unique populations with abnormalities in this chromosome, such as women with Turner syndrome, may offer clues into this illness.
 ...
PMID:Investigation of Turner syndrome in schizophrenia. 1089 17

A case of Klinefelter's syndrome with schizophrenia-like symptoms is reported. He was given a diagnosis of schizophrenia at the age of 39. After being treated with medication for many years, he stopped taking them at the age of seventy-two and involuntary movements appeared in his limbs and the trunk. Upon admission to our hospital, he was experiencing delusion and psychosocial excitement. A physical examination showed him to be a thin man of 175.5 cm height, suffering from a mild degree of gynecomastia, testicular atrophy. Serum LH and FSH were both high 10.9 and 47.8 mU/ml respectively. Serum testosterone concentration was 0.2 ng/ml, much lower than the normal range (2.7-10.7 ng/ml). On the Wechsler adult intelligence scale (Revision), his total IQ was 103 (performance IQ 100, verbal IQ105). Karyotype analysis revealed an XXY pattern. Although slight auditory hallucinations remained, the delusional symptoms as well as the involuntary movements diminished after the administration of psychotrophics. Personality changes such as apathy and abulia was subsided. The psychological symptoms were very similar to these of cases in other reports of Klinefelter's syndrome associated with schizophrenia-like symptoms. Some reports about the relationships between sex hormones and schizophrenia including other psychotic disorders suggest that the X-chromosome plays an important part in the mechanism of psychosocial symptoms and in the prognosis in Klinefelter's syndrome.
 ...
PMID:[A case of Klinefelter's syndrome with schizophrenia-like symptoms]. 1099 33

The effect of a single dose of 10 mg olanzapine on healthy volunteers of both sexes was examined using polysomnography and power spectral analysis. The structure and continuity of sleep were unaffected by olanzapine in both sexes. The increase in both actual sleep time and slow wave sleep in females correlated with the increase in theta power, while delta power was not significantly elevated, suggesting that theta power may be a sensitive indicator of changes in sleep. The changes in sleep had the same tendency in men, but they were not significant. The difference between the sexes could not be explained by differences in body mass index. Olanzapine affects sleep probably through 5-HT(2C) receptors. The receptor gene is located on the X-chromosome, inducing an allelic difference between the females and males. This difference may contribute to the different effects of olanzapine on sleep. Olanzapine seems to preserve the normal structure of sleep and increase the amount of slow-wave sleep, which might be of additional benefit in treatment of schizophrenia. The effective clinical dose may be lower for females than males.
 ...
PMID:Effect of a single-dose of olanzapine on sleep in healthy females and males. 1213 1

HOPA is a X-chromosome gene that encodes an essential nuclear receptor co-activator. Previously, we have demonstrated that an exonic polymorphism, termed HOPA(12bp), in the Opa (Opposite Paired) domain of this gene that is critical for neuronal growth and differentiation is associated with a low risk for schizophrenia. But curiously, we have also noted that all HOPA(12bp) probands have the same haplotype immediately surrounding the HOPA(12bp), and other investigators have found evidence of population stratification with the HOPA(12bp) allele. Since deleterious alleles are weeded from the population, and the HOPA(12bp) allele is not rare, these prior findings suggest the possibility that positive selection may be occurring with respect to the HOPA(12bp) allele and that unique phenotypic features may be associated with this allele. To test these hypotheses, we analyzed symptom data collected from schizophrenic probands and conducted haplotyping studies around the HOPA(12bp) polymorphism. Consistent with our hypotheses, genotyping studies of 43 unrelated HOPA(12bp) males and 137 HOPA(wild) males demonstrated that the HOPA(12bp) allele is associated with a large conserved DNA haplotype that extends over several genes known to be critical for human survival. Furthermore, ANOVA analysis of symptom data demonstrated that HOPA(12bp) schizophrenic probands (n = 14) have significantly lower severity of negative symptoms (P < 0.002) and better attention (P < 0.002) than matched controls (n = 30). Taken together, these findings further refine the behavioral endophenotype associated with the HOPA(12bp) allele and suggest that the sequence surrounding HOPA may need to be considered to fully understand the molecular basis of the phenotype associated with the HOPA(12bp) allele.
 ...
PMID:Association of the HOPA12bp allele with a large X-chromosome haplotype and positive symptom schizophrenia. 1510 74


1 2 Next >>