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)

The gene encoding the human mitochondrial citrate transporter designated SLC20A3 was mapped to chromosome 22 by analyzing its segregation in a panel of human-hamster somatic cell hybrids. This assignment was confirmed by fluorescence in situ hybridization to metaphase chromosomes, and the gene was further localized to band 22q11.21. The gene is located in a critical region associated with allelic losses in a variety of clinical syndromes, including DiGeorge syndrome, velo-cardio-facial syndrome and a subtype of schizophrenia.
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PMID:The human mitochondrial citrate transporter gene (SLC20A3) maps to chromosome band 22q11 within a region implicated in DiGeorge syndrome, velo-cardio-facial syndrome and schizophrenia. 868 95

Previous studies have demonstrated possible linkage between chromosome 22 and one of the hypothesized schizophrenia susceptibility genes. Interpretation of these data, however, is not straightforward: although not significant at the level traditionally accepted to demonstrate linkage, reported lod scores were greater than should have occurred by chance for an unlinked marker based on simulation studies. Further, these studies used sample populations which were either of mixed nationality and ethnicity, or mixed ethnic ancestry from one country. We therefore tested for linkage between highly polymorphic chromosome 22 markers and schizophrenia in a sample of southern African Bantu-speaking black families, a population known to have diverged within the last 2,000 years. We also tested one candidate locus, the gene for the soluble form of catechol-O-methyl transferase (COMT) located at 22q11, which has been suggested as the cause of psychiatric symptoms observed in velo-cardio-facial syndrome (VCFS, including DiGeorge syndrome), and which is known to be functionally as well as genetically polymorphic. There is no evidence to support the linkage of markers on chromosome 22 to susceptibility to schizophrenia in this population, using either parametric or nonparametric analysis.
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PMID:No evidence for linkage of chromosome 22 markers to schizophrenia in southern African Bantu-speaking families. 895 Apr 8

To investigate molecular and clinical aspects of conotruncal anomaly face (CAF), we studied the correlation between deletion size and phenotype and the mode of inheritance in 183 conotruncal anomaly face syndrome (CAFS) patients. Hemizygosity for a region of 22ql1.2 was found in 180 (98%) of the patients with CAFS by fluorescence in situ hybridization (FISH) using the N25(D22S75) DiGeorge critical region (DGCR) probe. No hemizygosity was found in three (2%) of the patients with CAFS by FISH using nine DiGeorge critical region probes and a SD1OP1 probe (DGA II locus). None of these three patients had mental retardation and just one had nasal intonation, which was observed in almost all of the 180 CAFS patients who carried deletions (mental retardation, 92%; nasal voice, 88%). Nineteen of 143 families (13%) had familial CAFS and 16 affected parents (84%) were mothers. Although only two of the affected parents had cardiovascular anomalies, the deletion size in the 16 affected parents and their affected family members, who were studied by FISH analysis, was the same. It indicates that extragenic factors may play a role in the genesis of phenotypic variability, especially in patients with cardiovascular anomalies. No familial cases were found among CAFS patients with absent thymus/DiGeorge anomaly (DGA). Also, in all 18 CAFS patients with completely absent thymus/DGA and all 6 CAFS patients with schizophrenia, it was revealed that the deletion was longer distally. A study of the origin of the deletion using microsatellite analyses in 48 de novo patients showed that in 65% of CAFS patients it was maternal, while in 64% of DGA patients it was paternal. The findings of this study indicated that CAF was almost always associated with the deletion of 22ql1.2. As well as the major features of the syndrome, other notable extracardiac anomalies were found to be susceptibility to infection, schizophrenia, atrophy or dysmorphism of the brain, thrombocytopenia, short stature, facial palsy, anal atresia, and mild limb abnormalities.
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PMID:Molecular and clinical study of 183 patients with conotruncal anomaly face syndrome. 973 80

Deletions or rearrangements of human chromosome 22q11 lead to a variety of related clinical syndromes such as DiGeorge syndrome (DGS) and velo--cardiofacial syndrome (VCFS). In addition, patients with 22q11 deletions have an increased incidence of schizophrenia and several studies have mapped susceptibility loci for schizophrenia to this region. Human molecular genetic studies have so far failed to identify the crucial genes or disruption mechanisms that result in these disorders. We have used gene targeting in the mouse to delete a defined region within the conserved DGS critical region (DGCR) on mouse chromosome 16 to prospectively investigate the role of the mouse DGCR in 22q11 syndromes. The deletion spans a conserved portion ( approximately 150 kb) of the proximal region of the DGCR, containing at least seven genes ( Znf74l, Idd, Tsk1, Tsk2, Es2, Gscl and Ctp ). Mice heterozygous for this deletion display no findings of DGS/VCFS in either inbred or mixed backgrounds. However, heterozygous mice display an increase in prepulse inhibition of the startle response, a manifestation of sensorimotor gating that is reduced in humans with schizophrenia. Homozygous deleted mice die soon after implantation, demonstrating that the deleted region contains genes essential for early post-implantation embryonic development. These results suggest that heterozygous deletion of this portion of the DGCR is sufficient for sensorimotor gating abnormalities, but not sufficient to produce the common features of DGS/VCFS in the mouse.
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PMID:Deletion of 150 kb in the minimal DiGeorge/velocardiofacial syndrome critical region in mouse. 1054 3

Deletion of chromosome 22q11 concerns nearly 1/5.000 births, and is the most frequent interstitial microdeletion. The deletion generates various phenotypes which were initially regarded as distinct syndromes. 1) Di George syndrome was described in 1962 by immunologists, and associates thymic and parathyroid hypoplasia, cardiac malformation, and dysmorphic face; the prognosis is severe, as Di George syndrome is a life-threatening condition. 2) The velocardiofacial syndrome was described in 1978 by stomatologists, and associates palate abnormalities, cardiac malformations, dysmorphic faces, and learning disabilities. 3) The Takao syndrome was described in the late seventies by cardiologists as a clinical condition associating cardiac abnormalities and dysmorphic faces. During the nineties, a common molecular etiology was identified, and a new name proposed: CATCH 22, an acronyme for Cardiac abnormalities, Abnormal face, Thymic hypoplasia, Cleft palate, Hypocalcemia, deleted chromosome 22. Furthermore, new phenotypes have been recently recognized, most of them belonging to the psychiatric spectrum. Descriptive studies of large samples of children with 22q11 deletion, conducted, both in the United States and european countries, have shown the following pattern of associated symptoms:--abnormal face (100%), which expression varies with age, and can be discrete;--cardiac abnormalities (84%), including cardiac malformations of conotroncal types;--mouth abnormalities (49%), including cleft palate (14%), and velar dysfunction (20%);--urinary tract abnormalities (36%), including ureteric reflux, lung dysplasia;--transitory hypocalcemia (60%) mostly during infancy, and due to transitory hypoparathyroid dysfunction;--seizures (21%), which are usually a consequence of hypocalcemia;--immunodeficiency (1%), which worsens the prognosis. Deletion of chromosome 22q11 has been also associated with various psychiatric phenotypes, which can be classified into two groups, developmental abnormalities and psychiatric conditions. The great majority of patients with the deletion exhibit impairment of language and motor development, mild mental retardation, persistent coordination deficits, and poor academic performance. The deletion of chromosome 22q11 is also associated with high frequency of behavioral disorder with attention deficit during childhood, and with high frequency of psychotic disorder (bipolar disorder, and schizophrenia) during adolescence and young adulthood. The link between the 22q11 deletion and schizophrenia has been also supported by recent studies showing that the rate of 22q11 deletion in adults with schizophrenia (2%) is higher than it is in the general population. The rate may even be higher (6%) in subjects with childhood onset schizophrenia. The present work reviews the psychiatric literature associated with 22q11 deletion. We also report a case of 22q11 deletion in a 17-year-old girl that was initially diagnosed as paranoid schizophrenia. We will discuss the diagnostic, prognostic, and therapeutic consequences that such a genetic diagnosis implies. In the case reported here, transitory hypocalcemia induced: 1) dystonic symptoms that was believed to be catatonic symptoms or neuroleptic secondary effects, by clinicians; 2) a poor response to neuroleptic medication.
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PMID:[Microdeletion 22q11: apropos of case of schizophrenia in an adolescent]. 1129 38

Schizophrenia or schizoaffective disorders are often found in patients affected by DiGeorge/velo-cardio-facial syndrome (DGS/VCFS) as a result of hemizygosity of chromosome 22q11.2. We evaluated the UFD1L gene, mapping within the DGS/VCFS region, as a potential candidate for schizophrenia susceptibility. UFD1L encodes for the ubiquitin fusion degradation 1 protein, which is expressed in the medial telencephalon during mouse development. Using case control, simplex families (trios), and functional studies, we provided evidence for association between schizophrenia and a single nucleotide functional polymorphism, -277A/G, located within the noncoding region upstream the first exon of the UFD1L gene. The results are supportive of UFD1L involvement in the neurodevelopmental origin of schizophrenia and contribute in delineating etiological and pathogenetic mechanism of the schizophrenia subtype related to 22q11.2 deletion syndrome.
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PMID:Association study of a promoter polymorphism of UFD1L gene with schizophrenia. 1149 70

22q11 deletion syndrome (22qDS), also known as DiGeorge or velocardiofacial syndrome (DGS/VCFS), is a relatively common genetic anomaly that results in malformations of the heart, face and limbs. In addition, patients with 22qDS are at significant risk for psychiatric disorders as well, with one in four developing schizophrenia, and one in six developing major depressive disorders. Like several other deletion syndromes associated with psychiatric or cognitive problems, it has been difficult to determine which of the specific genes in this genomic region may mediate the syndrome. For example, patients with different genomic deletions within the 22q11 region have been found that have similar phenotypes, even though their deletions do not compromise the same set of genes. In this review, we discuss the individual genes found in the region of 22q11 that is commonly deleted in 22qDS patients, and the potential roles each of these genes may play in the syndrome. Although many of these genes are interesting candidates by themselves, we hypothesize that the full spectrum of anomalies associated with 22qDS may result from the combined result of disruptions to numerous genes within the region that are involved in similar developmental or cellular processes.
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PMID:22q11 DS: genomic mechanisms and gene function in DiGeorge/velocardiofacial syndrome. 1217 81

The increased prevalence of schizophrenia among patients with the 22q11 interstitial deletion associated with DiGeorge syndrome has suggested the existence of a susceptibility gene for schizophrenia within the DiGeorge syndrome chromosomal region (DGCR) on 22q11. Screening for genomic rearrangements of 23 genes within or at the boundaries of the DGCR in 63 unrelated schizophrenic patients and 68 unaffected controls, using quantitative multiplex PCR of short fluorescent fragments (QMPSF), led us to identify, in a family including two schizophrenic subjects, a heterozygous deletion of the entire PRODH gene encoding proline dehydrogenase. This deletion was associated with hyperprolinemia in the schizophrenic patients. In addition, two heterozygous PRODH missense mutations (L441P and L289M), detected in 3 of 63 schizophrenic patients but in none among 68 controls, were also associated with increased plasma proline levels. Segregation analysis within the two families harboring respectively the PRODH deletion and the L441P mutation showed that the presence of a second PRODH nucleotide variation resulted in higher levels of prolinemia. In two unrelated patients suffering from severe type I hyperprolinemia with neurological manifestations, we identified a homozygous L441P PRODH mutation, associated with a heterozygous R453C substitution in one patient. These observations demonstrate that type I hyperprolinemia is present in a subset of schizophrenic patients, and suggest that the genetic determinism of type I hyperprolinemia is complex, the severity of hyperprolinemia depending on the nature and number of hits affecting the PRODH locus.
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PMID:PRODH mutations and hyperprolinemia in a subset of schizophrenic patients. 1221 52

Haploinsufficiency syndromes, such as the deletion 22q11, the velo-cardio-facial or DiGeorge/Shprintzen syndrome characterised by chromosome 22q11 deletion, show marked variability in the clinical features. This variability may be due to chance fluctuations in expression of genes in the deleted segment, which tend to have more impact if only one copy of the gene is present. The apparent association between deletion 22q11 and schizophrenia indicates a role for a gene within the deletion in signal transduction in the brain.
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PMID:[Phenotypic variability: genetics and chance--deletion 22q11 and schizophrenia]. 1242 63

Schizophrenia or schizoaffective disorders are quite common features in patients with DiGeorge/velocardiofacial syndrome (DGS/VCFS) as a result of hemizygosity of chromosome 22q11.2. We evaluated the PCQAP gene, which maps within the DGS/VCFS interval, as a potential candidate for schizophrenia susceptibility. PCQAP encodes for a subunit of the large multiprotein complex PC2, which exhibits a coactivator function in RNA polymerase II mediated transcription. Using a case-control study, we searched association between schizophrenia and the intragenic coding trinucleotide polymorphism. The distribution of the CAG repeat alleles was significantly different between patients and controls with the Mann-Whitney test (z = -2.5694, P = 0.0051; schizophrenics: n = 378, W = 161,002.5, Mean rank = 425.9325; controls: n = 444, W = 177,250.5, Mean rank = 399.2128). This result may indicate a possible involvement of the multiprotein complex PC2 in schizophrenia susceptibility.
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PMID:Association study between CAG trinucleotide repeats in the PCQAP gene (PC2 glutamine/Q-rich-associated protein) and schizophrenia. 1249 10


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