Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0025362 (mental retardation)
 15,878 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The protein EP300 and its paralog CREBBP (CREB-binding protein) are ubiquitously expressed transcriptional co-activators and histone acetyl transferases. The gene EP300 is essential for normal cardiac and neural development, whereas CREBBP is essential for neurulation, hematopoietic differentiation, angiogenesis and skeletal and cardiac development. Mutations in CREBBP cause Rubinstein-Taybi syndrome, which is characterized by mental retardation, skeletal abnormalities and congenital cardiac defects. The CBP/p300-interacting transactivator with ED-rich tail 2 (CITED2) binds EP300 and CREBBP with high affinity and regulates gene transcription. Here we show that Cited2-/- embryos die with cardiac malformations, adrenal agenesis, abnormal cranial ganglia and exencephaly. The cardiac defects include atrial and ventricular septal defects, overriding aorta, double-outlet right ventricle, persistent truncus arteriosus and right-sided aortic arches. We find increased apoptosis in the midbrain region and a marked reduction in ErbB3-expressing neural crest cells in mid-embryogenesis. We show that CITED2 interacts with and co-activates all isoforms of transcription factor AP-2 (TFAP2). Transactivation by TFAP2 isoforms is defective in Cited2-/- embryonic fibroblasts and is rescued by ectopically expressed CITED2. As certain Tfap2 isoforms are essential in neural crest, neural tube and cardiac development, we propose that abnormal embryogenesis in mice lacking Cited2 results, at least in part, from its role as a Tfap2 co-activator.
 ...
PMID:Cardiac malformations, adrenal agenesis, neural crest defects and exencephaly in mice lacking Cited2, a new Tfap2 co-activator. 1169 77

Rubinstein-Taybi syndrome (RSTS) is a distinct dominant disorder characterized by short stature, typical face, broad angulated thumbs and halluces, and mental retardation. The RSTS can be caused by chromosomal microdeletions and molecular mutations in the CREBBP gene; however, relatively few mutations have been reported to date. Here, we aimed to determine the rate of point mutations and other small molecular lesions in true RSTS and possible mild variants, by using genomic DNA sequencing. A consecutive series of patients including 17 patients from our previous study was investigated. We identified 19 causative mutations of CREBBP in a total of 45 patients representing three different diagnostic groups: (a) 17 mutations in 30 patients with unequivocal RSTS (detection rate 56.6%), (b) two mutations in eight patients with features suggestive of RSTS ("moderate or incomplete RSTS", detection rate 25%), and (c) no mutation in seven patients with undiagnosed syndromes and isolated features of RSTS. In general, the mutations were distributed without hot spots and most were unique; however, three recurrent mutations (R370X, R1664H, and N1978S) were identified. Furthermore, we detected 15 different intragenic polymorphisms, including two non-synonymous coding polymorphisms, L551I and Q2208H. We report not only the highest detection rate (56.6%) of CREBBP mutations in patients with RSTS to date, but also the second missense mutation (N1978S) in a patient with moderate or incomplete RSTS. Previous studies have identified cytogenetic deletions in the CREBBP gene in eight to 12% of patients and very recently, Roelfsema et al. reported EP300 gene mutations in three of 92 (3.3%) patients with either true RSTS or different syndromes resembling RSTS. Our 56.6% detection rate of molecular mutations in CREBBP in patients with unequivocal RSTS supports the new concept that RSTS is a genetically heterogeneous disorder and furthermore, indicates that RSTS may be caused by gene/s other than CREBBP in up to 30% of cases.
 ...
PMID:DNA sequencing of CREBBP demonstrates mutations in 56% of patients with Rubinstein-Taybi syndrome (RSTS) and in another patient with incomplete RSTS. 1602 71

The Rubinstein-Taybi syndrome (RSTS, MIM 180849), a dominant Mendelian disorder with typical face, short stature, skeletal abnormalities, and mental retardation, is usually caused by heterozygous mutations of the CREBBP gene, but recently, EP300 gene mutations were reported in three individuals. Using quantitative PCR (for the CREBBP and EP300 genes) and genomic sequencing (for the EP300 gene), we studied here 13 patients who had shown no mutation after genomic sequencing of the CREBBP gene in a previous investigation. Two new disease-causing mutations were identified, including a partial deletion of CREBBP and a 1-bp deletion in EP300, c.7100delC (p.P2366fsX2401). The 1-bp deletion represents the fourth EP300 mutation reported to date and was identified in a patient with non-classical RSTS. Based on the very similar structure of the CREBBP and EP300 genes and the higher rate of single-nucleotide polymorphisms in EP300 (2.23 per individual) as compared to CREBBP (0.71 per individual) (P>0.001, Wilcoxon test), it may be assumed that EP300 gene mutations should be as frequent as CREBBP gene mutations. Based on the location of the EP300 gene mutations identified so far (outside the histone acetyl transferase domain) and the observed (although not very striking) phenotypical differences with the EP300 mutations, we propose that most EP300 mutations could be associated with other phenotypes, not classical RSTS.
 ...
PMID:Confirmation of EP300 gene mutations as a rare cause of Rubinstein-Taybi syndrome. 1729 36

Rubinstein-Taybi syndrome is characterised by mental retardation, growth retardation and a particular dysmorphology. The syndrome is rare, with a frequency of approximately one affected individual in 100,000 newborns. Mutations in two genes - CREBBP and EP300 - have been identified to cause the syndrome. These two genes show strong homology and encode histone acetyltransferases (HATs), which are transcriptional co-activators involved in many signalling pathways. Loss of HAT activity is sufficient to account for the phenomena seen in Rubinstein-Taybi patients. Although some mutations found in CREBBP are translocations, inversions and large deletions, most are point mutations or small deletions and insertions. Mutations in EP300 are comparatively rare. Extensive screening of patients has revealed mutations in CREBBP and EP300 in around 50% of cases. The cause of the syndrome in the remaining patients remains to be identified, but other genes could also be involved. Here, we describe the clinical presentation of Rubinstein-Taybi syndrome, review the mutation spectrum and discuss the current understanding of causative molecular mechanisms.
 ...
PMID:Rubinstein-Taybi syndrome: clinical and molecular overview. 1794 8

Rubinstein-Taybi syndrome (RTS) is a rare multiple congenital anomaly/intellectual impairment syndrome. Loss of function in CREBBP or EP300 genes has been found in about 50% of patients with RTS. Genotype-phenotype correlations were investigated in 93 patients meeting diagnostic criteria for RTS during 2 international RTS family conferences. Mutation analysis of CREBBP was performed on all 31 coding exons and exon-intron junctions; a subset of patients had FISH analysis for large deletions. A total of 64 different variations were observed in the DNA sequence, and determined to be definitive mutations in 52 patients (56%). Mutations detected included: 10 missense mutations; 36 truncating or splice-site mutations; and 6 large deletions detectable by FISH. Fourteen patients had synonymous changes of unknown significance. The majority of mutations affected the HAT domain of CREBBP or predicted termination of the protein before the HAT region. Extensive phenotypic data were collected on each patient and analyzed to determine correlations with mutation types, that is, truncating, large deletions, single amino acid substitutions, or no CREBBP mutation. All four groups displayed the characteristic facial and thumb dysmorphology. Growth retardation in height and weight was seen more frequently in patients with no CREBBP mutation; seizure disorder was more frequent in those with CREBBP mutations. Degree of mental retardation was similar in all groups, although there was a trend toward lower IQ and autistic features in patients with large deletions. Similarity in phenotype between the groups implies that the several genes involved in causing RTS likely have effects through the same pathway.
 ...
PMID:Genotype-phenotype correlations in Rubinstein-Taybi syndrome. 1879 86

Rubinstein-Taybi syndrome (RSTS) is a rare autosomal dominant genetic disease and is characterized by mental retardation, distinctive facial features, broad and often angulated thumbs and great toes, short stature, and growth retardation. CREBBP and EP300 are the only genes currently known to be associated with RSTS. Mutations in CREBBP and EP300 were identified in approximately 50% and 3% of RSTS patients, respectively. To date, most of CREBBP mutations were de novo mutations and the recurrence rate in a family was low. Families with more than one affected child are extremely rare. In this study, we have shown a family with two affected siblings; the same mutation was found in both siblings. However, the mutation was not found in the blood or saliva DNA samples from the parents, suggesting the mechanism of germ-line mosaicism. In addition, we identified low-level mosaicism of a CREBBP mutation in the father from a second family with one affected child. Among the three analyzed tissue samples from the father, low-level mosaicism is present only significantly in the blood sample. We hypothesize mutations in CREBBP in these two families occur in the postzygotic stage in one of the parents (one generation ahead) of the affected individual. Additional family studies are required to determine how common somatic and/or gonadal mosaicism is present in RSTS patients.
 ...
PMID:Somatic and germ-line mosaicism in Rubinstein-Taybi syndrome. 2035 23

The Rubinstein-Taybi syndrome (RTS; OMIM 180849) is a well-defined mental retardation/multiple congenital anomalies (MR/MCA) syndrome characterized by postnatal growth retardation, microcephaly, specific facial features, broad thumbs and halluces, and MR of variable degree. Ten percent of patients with RTS have a microdeletion 16p13.3, 40-50% carry a mutation of the CREBBP gene and another 3% have a mutation in the EP300 gene. In the remaining patients with clinically suspected RTS no mutation can be detected. Here we describe two patients with an RTS phenotype, one with a mutation in the CREBBP gene and the other without a detectable CREBBP or EP300 mutation and without a chromosomal imbalance on high-resolution arrays. Both patients present with the characteristic facial RTS phenotype, broad thumbs and big toes, mild MR, formation of keloids and glaucoma, but without postnatal growth retardation or microcephaly. In addition, they have both congenital camptodactyly of third (and fourth) fingers, which has not reported in RTS previously. We suggest that they represent a clinical subtype of RTS.
 ...
PMID:Two adults with Rubinstein-Taybi syndrome with mild mental retardation, glaucoma, normal growth and skull circumference, and camptodactyly of third fingers. 1993 80

Rubinstein-Taybi syndrome (RTS) is characterized by mental retardation, broad thumbs and great toes and a recognizable craniofacial phenotype. Causative mutations have been described in the CREBBP and EP300 genes. Here we present a 19-year-old woman and an unrelated 3-year-old boy, both with broad thumbs and halluces, but with facial aspects distinct from those of typical RTS. The woman had a marked learning disability, but no mental retardation. We identified a de novo c.7100delC mutation in EP300 (which predicts p.P2366RfsX35) in the woman and an apparently de novo c.638delG mutation in the boy, which predicts p.G213EfsX6. Mutations in EP300 are a known but rare cause of RTS. Only five other patients have been reported. We propose that individuals with EP300 mutations may exhibit a slightly different phenotype compared to individuals with CREBBP mutations, with milder cognitive impairment, more pronounced microcephaly, absent or mild downslanting of palpebral fissures, distinct arched eyebrows, and greater degree of retrognathia.
 ...
PMID:Two patients with EP300 mutations and facial dysmorphism different from the classic Rubinstein-Taybi syndrome. 2094 5

Rubinstein-Taybi syndrome (RTS) is a rare autosomal dominant genetic disorder and is characterized by mental retardation, distinctive facial features, broad and often angulated thumbs and great toes. We report on a 7 year old boy with classical Rubinstein-Taybi syndrome. His facial and clinical features were very typical, including broad thumbs with radial angulation and broad great toes. Rigorous genetic analysis of the CREBBP and EP300 genes using DNA sequencing and multiple ligation-dependent probe amplification (MLPA) revealed no causative mutation in this boy, only a hitherto unreported but paternally inherited heterozygous sequence alteration, c.506 1+9C>T in IVS 30-31, which most likely represents a normal variant (NetGene 2 splice prediction software). We question if this boy could have a hitherto undetectable mutation type.
 ...
PMID:A boy with classical Rubinstein-Taybi syndrome but no detectable mutation in the CREBBP and EP300 genes. 2230 93

Rubinstein-Taybi syndrome is characterized by distinctive facial and limb features and is associated with several types of tumors. A 29-yr-old woman with this syndrome presented with a large, complex ovarian mass. She was subsequently diagnosed with a low-grade serous carcinoma of the ovary and an endometrioid adenocarcinoma of the uterus. Rubinstein-Taybi syndrome is an autosomal dominant, multiple congenital anomalies-mental retardation syndrome. Two genes, CREBBP and EP300, have been found to be associated with this disorder, although some cases do not have an identifiable cause. These genes code for proteins that acetylate histone tails, an epigenetic modification that serves to control transcription. They also serve as cofactors to several transcription factors and modulate p53. Although these patients have a predisposition to benign and malignant neoplasms, no malignant gynecologic neoplasm has been described thus far. Although no significant evidence linking CREBBP and EP300 to gynecologic malignancies has yet been found, some studies have suggested that hypoacetylation of histones may be involved in endometrial and ovarian carcinomas.
...
PMID:Synchronous ovarian and endometrial carcinomas in a patient with Rubinstein-Taybi syndrome: a case report and literature review. 2567 81


1 2 Next >>