1/7. child with velocardiofacial syndrome and del (4)(q34.2): another critical region associated with a velocardiofacial syndrome-like phenotype.We report on a child with congenital heart disease (atrial septal defect, ventricular septal defect, pulmonic stenosis), submucosal cleft palate, hypernasal speech, learning difficulties, and right fifth finger anomaly manifestations, consistent with velocardiofacial syndrome (VCFS); however, cytogenetic analysis demonstrated a small terminal deletion of the segment 4q34.2 to 4qter. Fluorescent in situ hybridization did not identify a deletion of the critical region associated with VCFS. In previously reported 4q deletions with a breakpoint distal to 4q34.2, no cardiac defects or cleft of palate were reported. Our patient has a deletion of 4q34.2 to 4qter and has palate and cardiac involvement and minor learning difficulties, which implies that genes involved in heart and palate development lie distal to 4q34.2, and that the critical region for more severe mental retardation on 4q may reside proximal to 4q34.2. These results suggest that a distal 4q deletion can lead to a phenotype similar to VCFS and emphasizes the importance of searching for other karyotype abnormalities when a VCFS-like phenotype is present and a 22q deletion is not identified.- - - - - - - - - - ranking = 1keywords = hybridization (Clic here for more details about this article) |
2/7. A family with a grand-maternally derived interstitial duplication of proximal 15q.About 1% of individuals with autism or types of pervasive developmental disorder have a duplication of the 15q11-q13 region. These abnormalities can be detected by routine G-banded chromosome study, showing an extra marker chromosome, or demonstrated by fluorescence in situ hybridization (FISH) analysis, revealing an interstitial duplication. We report here the molecular, cytogenetic, clinical and neuropsychiatric evaluations of a family in whom 3 of 4 siblings inherited an interstitial duplication of 15q11-q13. This duplication was inherited from their mother who also had a maternally derived duplication. Affected family members had apraxia of speech, phonological awareness deficits, developmental language disorder, dyslexia, as well as limb apraxia but did not have any dysmorphic clinical features. The observations in this family suggest that the phenotypic manifestations of proximal 15q duplications may also involve language-based learning disabilities.- - - - - - - - - - ranking = 1keywords = hybridization (Clic here for more details about this article) |
3/7. Inherited ring chromosome 8 without loss of subtelomeric sequences.We report the first case of inherited ring chromosome 8 syndrome without loss of subtelomeric sequences. The proband is a 6 1/2-year-old boy with short stature, microcephaly, mild mental retardation, and behavioral problems including hyperactivity and attention deficit. His mother presented the same physical features but intelligence was normal. family history also revealed an uncle and a grandmother, with short stature and microcephaly. Moderate mental retardation was reported in the uncle. Karyotypes and fluorescence in situ hybridization (FISH) analyses were performed on peripheral blood lymphocytes for both child and mother. The child's karyotype was reported as 46,XY,r(8)(p23q24.3)[24]/45,XY,-8[2] and the mother's karyotype 46,XX,r(8)(p23q24.3)[22]/45,XX,-8[2]/47,XX,r(8)(p23q24.3), r(8)(p23q24.3)[1]. FISH studies showed no deletion of subtelomeric sequences for both child and mother indicating that no or little chromosomal euchromatic material has been deleted. These findings indicate that ring chromosome 8 without loss of subtelomeric sequences can be inherited and that carriers in a same family present with cognitive function ranging from mild mental retardation to normal intelligence.- - - - - - - - - - ranking = 1keywords = hybridization (Clic here for more details about this article) |
4/7. Disruption of a brain transcription factor, NPAS3, is associated with schizophrenia and learning disability.A mother and daughter diagnosed with schizophrenia and schizophrenia co-morbid with mild learning disability, respectively, possess a balanced reciprocal translocation t(9,14)(q34.2;q13). fluorescence in situ hybridization (FISH) with YAC, BAC, and cosmid probes indicate that the chromosome 14q13 breakpoint disrupts a large gene, NPAS3, encoding a CNS expressed transcription factor of the basic helix-loop-helix PAS (bHLH-PAS) gene family. By analogy with other members of the bHLH-PAS family, the putative truncated protein generated from the disrupted gene locus may have a dominant negative effect. The 14q13 region was previously identified by a linkage study of an inherited neurodegenerative condition, idiopathic basal ganglia calcification (IBGC or Fahr syndrome, OMIM:213600/606656), which is often co-morbid with psychosis. Sequencing of the gene in a third patient diagnosed with IBGC, schizophrenia, and mild learning disability did not reveal functional mutations.- - - - - - - - - - ranking = 1keywords = hybridization (Clic here for more details about this article) |
5/7. Characterization of a familial balanced rec(13) in a child with mild MR and his half-sibling with two structurally rearranged chromosomes 13.In this report, we describe a 7-year-old child with mild mental retardation, developmental delay, and learning disabilities. His karyotype contained a rearrangement of chromosome 13, which appeared to include a duplication of 13q31-qter and a deletion of 13p12-pter regions. The chromosomal origin of the additional material was confirmed by fluorescence in situ hybridization (FISH) using a whole chromosome painting probe specific for chromosome 13. family studies showed that his mother carried a balanced inversion of chromosome 13 and that his half-brother carried the balanced pericentric inversion of chromosome 13 from his mother as well as another structural rearrangement involving chromosome 13 presumably from his father. The findings from this study suggested that the proband's abnormal 13 resulted from an unbalanced crossing-over between the normal and maternal inverted chromosome 13.- - - - - - - - - - ranking = 1keywords = hybridization (Clic here for more details about this article) |
6/7. Normal adaptive function with learning disability in duplication 8p including band p22.Duplication 8p usually results in a syndrome characterized by profound mental retardation, mild facial anomalies, and malformations of hand, heart, and brain. We report on a large kindred segregating a Y;8 translocation in whom several individuals have duplication 8p22-->8pter. These individuals have normal adaptive function despite their unbalanced karyotype. The family was studied with G-banding and fluorescent in situ hybridization (FISH) using probes to chromosomes 8 and Y. Comparison of this family with other reported cases defines a mild clinical outcome for trisomy 8p22-->8pter in contrast to the severe findings when the duplication involves a longer, more proximal segment.- - - - - - - - - - ranking = 1keywords = hybridization (Clic here for more details about this article) |
7/7. Childhood-onset schizophrenia associated with parkinsonism in a patient with a microdeletion of chromosome 22.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.- - - - - - - - - - ranking = 1keywords = hybridization (Clic here for more details about this article) |