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)

We report the results of two studies examining the genetic overlap between schizophrenia and velocardiofacial syndrome. In study A, we characterize two interstitial deletions identified on chromosome 22q11 in a sample of schizophrenic patients. The size of the deletions was estimated to be between 1.5 and 2 megabases. In study B, we examine whether variations in deletion size are associated with the schizophrenic phenotype in velocardiofacial syndrome patients. Our results show that a region of the genome that has been previously implicated by genetic linkage analysis can harbor genetic lesions that increase the susceptibility to schizophrenia. Our findings should facilitate identification and cloning of the schizophrenia susceptibility gene(s) in this region and identification of more homogeneous subgroups of patients.
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PMID:Schizophrenia susceptibility associated with interstitial deletions of chromosome 22q11. 764 64

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

Velo-cardio-facial syndrome (VCFS) is a congenital anomaly characterized by multiple dysmorphisms, cleft palate, cardiac anomalies, and learning disabilities, that results from a microdeletion of chromosome 22q11. An increased prevalence of psychiatric illness has been observed, with both schizophrenia and bipolar disorder commonly being diagnosed. For these reasons, the VCFS region is an interesting candidate region for bipolar disorder. We examined this region in 17 bipolar families from three populations: 13 families from the general North American population (University of California, San Diego/University of British Columbia, UCSD/UBC), three larger families from New York, and a portion of Old Order Amish pedigree 110. Three microsatellite markers spanning 13 cM around the VCFS region were genotyped in all the families. A maximum lod score of 2.51 was obtained in the UCSD/UBC families under a dominant model at D22S303. In the combined family set, maximum lod scores of 1.68 and 1.28 were obtained at this marker under dominant and recessive models, respectively. Four additional markers were subsequently typed in selected positive families, and yielded positive lods at 6 of 7 markers spanning 18 cM in this region. Nonparametric, multipoint analyses using the affected pedigree member (APM) method also yielded suggestive evidence for linkage in both the UCSD/UBC family set (P = 0.0024) and in the combined families (P = 0.017). Affected sibpair analyses were similarly positive in the UCSD/UBC families (P = 0.017), and in the combined families (P = 0.004). These results are suggestive of a possible locus for bipolar disorder near the VCFS region on chromosome 22.
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PMID:Linkage studies suggest a possible locus for bipolar disorder near the velo-cardio-facial syndrome region on chromosome 22. 912 9

Velocardiofacial syndrome (VCFS) is associated with an increased frequency of schizophrenia and other types of psychiatric morbidity. In this study, we tried to identify a subgroup of schizophrenic patients with deletions in the VCFS region of the long arm of chromosome 22. For that purpose, we screened the records of two major general hospitals for patients with abnormalities characteristic of VCFS, such as cardiac anomalies and cleft palate, and cross-checked the data with the register of psychiatric hospitalizations in four psychiatric hospitals. Of the 24 patients that qualified, only seven patients could be studied. An additional eight schizophrenic inpatients were ascertained clinically, based on a working VCFS Clinical Scale. FISH studies and molecular analyses, using polymorphic markers from the VCFS region, documented hemizygosity of 22q11 in three out of 15 patients (20.0%). Increased awareness of psychiatrists to signs of VCFS among patients with psychiatric illnesses is encouraged, in order to direct molecular studies effectively. In order to cut down the cost of testing, we suggest screening suspected patients with a single marker, such as D22S941, and to study further only those who have a single electrophoretic band.
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PMID:Velocardiofacial manifestations and microdeletions in schizophrenic inpatients. 937 31

Since its first description almost a century ago schizophrenia with childhood onset, a rare yet devastating disorder, has been diagnosed in children as young as age 5. Recently, the velocardiofacial syndrome, whose underlying cause is interstitial deletions of 22q11.2, was found in 2 of 100 cases of schizophrenics with adult onset [Karayiorgou et al., Proc Natl Acad Sci USA 92: 7612-7616, 1995]. No study has documented the prevalence of velocardiofacial syndrome and the 22q11.2 deletion in a population of schizophrenics with childhood onset. Here we describe the result of such a study in a sample originally selected for a trial of atypical antipsychotic drugs. A separate group of patients was also included in the study; they can best be accounted for as a variant of childhood-onset schizophrenia (COS) and had been provisionally termed "multidimensionally impaired." Fluorescent in situ hybridization screening of 32 COS and 21 multidimensionally impaired patients revealed 1 COS patient with an interstitial deletion spanning at least 2.5 megabases.
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PMID:Chromosome 22q11.2 interstitial deletions among childhood-onset schizophrenics and "multidimensionally impaired". 951 86

A man with intellectual disability presented with schizophrenia, hypocalcaemia, facial dysmorphism and cleft soft palate. Velo-cardio-facial syndrome was diagnosed and deletion at 22q11 was confirmed by fluorescent in situ hybridization.
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PMID:Velo-cardio-facial syndrome, schizophrenia and deletion at chromosome 22q11. 961 2

Genetic syndromes associated with deletions at chromosome 22q11 generally have been diagnosed during childhood based on a constellation of physical features. To investigate a reported association of velocardiofacial syndrome with psychotic disorders in adults, we assessed subjects with DSM-IV schizophrenia or schizoaffective disorder who were referred with two or more syndromal features (palatal, cardiac, facial, or other congenital anomalies, and/or learning difficulties). We report on 10 subjects (5 men and 5 women), mean age 27.2 (SD 6.0) years, who were found to have a 22q11 deletion at locus D22S75 using fluorescence in-situ hybridization (FISH). The mean age at onset of psychosis was 19.6 (SD 4.6) years. Symptoms and course of the psychotic illnesses were unremarkable, but additional signs such as temper outbursts were common. These adult subjects had significantly fewer major palatal (P = .0001) and conotruncal cardiac (P = .05) anomalies but the same high rate of learning difficulties as a sample with deletion 22q11 ascertained through a pediatric clinic [Lindsay et al. (1995): Am J Med Genet 57:514-522]. Minor congenital features and rate of transmitted cases were similar to those previously reported. These results replicate the association of a 22q11 deletion syndrome with schizophrenia and confirm the importance of ascertainment in influencing the phenotype found. The findings support a developmental gene in the 22q11 deletion region causing a complex phenotype which may include significant behavioral components that emerge over time. We support using the term "22q11 deletion syndrome (22DS)," which would encompass physical and psychiatric features, and could also be applied to describe a genetic subtype of schizophrenia.
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PMID:22q11 deletion syndrome in adults with schizophrenia. 967 80

The deletion of a gene or genes on chromosome 22q11 is responsible for the velocardiofacial syndrome (VCFS), which is associated with cardiac anomalies, short stature, palate abnormalities, learning disabilities, and developmental delay. Herein we describe a 30-year-old man with VCFS in whom a chronic psychotic disorder originated during childhood. A 10% rate of psychotic disorders has been reported in association with this genetic syndrome. In our patient, the clinical manifestation was complicated by extrapyramidal symptoms that predated the onset of psychotic symptoms. To our knowledge, extrapyramidal symptoms have not previously been reported in a patient with VCFS. The diagnosis of VCFS was confirmed with the fluorescence in situ hybridization probe for VCFS. The role of the atypical antipsychotic drug clozapine is discussed with respect to treating this patient who has severe psychotic symptoms coexisting with extrapyramidal symptoms and seizures. In light of the observation that patients with VCFS have an unexpectedly high rate of psychotic disorders, issues concerning the genetics of schizophrenia are intriguing.
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PMID:Childhood-onset schizophrenia associated with parkinsonism in a patient with a microdeletion of chromosome 22. 978 44

Velo-cardio-facial syndrome (VCFS) is caused by a microdeletion in the long arm of chromosome 22 and is associated with an increased frequency of schizophrenia and bipolar mood disorder. The purpose of this study was to investigate the genetic, physical, developmental and psychiatric features of schizophrenic patients with VCFS microdeletion. It describes the clinical findings in four schizophrenic inpatients with the characteristic chromosomal deletion. The four patients displayed delayed motor development, language deficits, learning disabilities, mental retardation, early age of onset, chronic and disabling course of illness and poor response to classical neuroleptic drugs and electroconvulsive therapy. Two patients benefited from treatment with clozapine. We suggest that schizophrenic patients with a history of delayed motor development, early onset of the disorder, history of learning disability, mental retardation, congenital cardiac anomalies and/or hypernasal speech should be screened for the velo-cardio-facial syndrome deletion. The implications of this study for psychiatric phenotype, nosology, disease mechanism, and possible new treatments in the future are discussed.
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PMID:Clinical characteristics of schizophrenia associated with velo-cardio-facial syndrome. 998 47

We present a mother and her son, both carrying a deletion of chromosome 22q.11.2. They manifest clinical heterogeneity. The mother has schizophrenia, an IQ of 70. Tetralogy of Fallot, a hypernasal voice, but does not have the characteristic facies. Her son has mild psychomotor developmental delay. Tetralogy of Fallot and mild facial features characteristic of VCFS.
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PMID:Familial deletion of 22q11.2. 1054 7


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