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

Two female neonates were diagnosed post partum with bilateral aniridia. The first patient had the familial form, caused by a point mutation in the paired box 6 (PAX6) gene. The second patient had a sporadic aniridia caused by a de novo microdeletion involving both the PAX6 gene as well as the Wilms tumour suppressor-I (WT1) gene. This made screening for the presence of a Wilms tumour necessary. The second patient died several months after birth, due to respiratory insufficiency. Aniridia is a rare developmental disorder of the eye, with absence of most of the iris tissue, caused by an abnormality in the PAX6 gene on chromosome 11p13. Familial aniridia is usually due to a point mutation of the PAX6 gene, which causes solely ocular abnormalities. Sporadic aniridia is caused by a de novo deletion or microdeletion of chromosome 11p13, which affects not only the PAX6 gene but also the adjacent WT1 gene. In these patients, the Wilms tumour, aniridia, genitourinary anomalies, and mental retardation (WAGR) syndrome can be present, and screening for a Wilms tumour is indicated. Unless previous investigation of a family member has demonstrated the WT1 gene to be normal, chromosome studies should always be performed in patients with aniridia.
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PMID:[Two neonates with congenital aniridia: the necessity of genetic investigation]. 1840 24

WAGR (Wilms tumor, Aniridia, Genitourinary malformations and mental Retardation) syndrome is a rare genomic disorder caused by deletion of the 11p14-p12 chromosome region. The majority of WAGR patients have mental retardation and behavioral problems, and more than 20% of the patients also have features of autism. While the Wilms tumor/genitourinary anomalies and aniridia are caused by deletion of WT1 and PAX6 respectively, the genomic cause of mental retardation and autism in WAGR syndrome remains unknown. Using oligonucleotide arrays, we have characterized the 11p14-p12 deletions in 31 patients and identified all the genes involved in each deletion. The deletions had sizes ranging from 4.9 to 23 Mb that encompass 18-62 genes (40 on average). In addition to WT1 and PAX6, all the patients had deletion of PRRG4 (transmembrane gamma-carboxyglutamic acid protein 4). The majority of them had deletion of BDNF (brain-derived neurotrophic factor) and SLC1A2 [solute carrier family 1 (glial high affinity glutamate transporter) member 2]. Deletion of BDNF and SLC1A2 occurred in patients with autism more frequently than in those without autism. Literature review on the functions of the genes suggests that haploinsufficiency of SLC1A2, PRRG4, and BDNF may contribute to mental retardation and behavioral problems. In particular, BDNF may modulate the risk of autism in WAGR patients as suggested by its link with Rett syndrome as a target of MECP2. We observed that all the de novo deletions occurred in the chromosome 11 inherited from the father in the families genotyped, implying a predisposition for de novo mutations occurring in spermatogenesis and possible involvement of imprinting in cognitive impairment in WAGR patients.
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PMID:Characterization of 11p14-p12 deletion in WAGR syndrome by array CGH for identifying genes contributing to mental retardation and autism. 1909 15

WAGR syndrome (Wilms' tumor, aniridia, genitourinary abnormalities and mental retardation) and Potocki-Shaffer syndrome are rare contiguous gene deletion syndromes caused by deletions of the 11p14-p12 chromosome region.We present a patient with mental retardation, unilateral cataract, bilateral ptosis, genital abnormalities, seizures and a dysmorphic face. Cytogenetic analysis showed a deletion on 11p that was further characterized using FISH and MLPA analyses. The deletion (11p13-p12) located in the area between the deletions associated with the WAGR and Potocki-Shaffer syndromes had a maximum size of 8.5 Mb and encompasses 44 genes. Deletion of WT1 explains the genital abnormalities observed. As PAX6 was intact the cataract observed cannot be explained by a deletion of this gene. Seizures have been described in Potocki-Shaffer syndrome while mental retardation has been described in both WAGR and Potocki-Shaffer syndrome. Characterization of this patient contributes further to elucidate the function of the genes in the 11p14-p12 chromosome region.
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PMID:11p Microdeletion including WT1 but not PAX6, presenting with cataract, mental retardation, genital abnormalities and seizures: a case report. 1922 35

The current paper presents a case of 14 months old girl with WAGR's syndrome. This syndrome is a genetic disorder characterized by the deletion at 11p13 locus which gives clinical presentation of aniridia, Wilms' tumor, genitourinary anomalies and mental retardation. Although WAGR's syndrome is a rare disorder, knowledge of its presentation is helpful in early diagnosis of nephroblastoma and may have impact on clinical outcome of the patient. Since aniridia may be the first symptom of WAGR's syndrome, it is recommended that all neonates with aniridia need to be screened for deletion of WT1 on chromosome 11p13. These with deletions should be monitored regularly for tumor development.
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PMID:[Sporadic aniridia and Wilm's tumor--a case report and review of recommendation for diagnostic approach in WAGR's syndrome]. 2147 84

The WAGR contiguous gene deletion syndrome is a combination of Wilms tumor, aniridia, genito-urinary abnormalities, and mental retardation. An 8.5-year-old girl was initially investigated at the age of 18 months for congenital bilateral aniridia, cataracts, glaucoma and epicantus. The ultrasound (US) scan showed polycystic kidney disease. FISH study revealed deletion of the WT1 and PAX6 gene in the 11p13 WAGR region. Forty days after the first kidney US, the second US revealed a 3 cm tumor in the right kidney: a Wilms tumour, treated successfully with the Wilm's tumor protocol. The authors conclude that the identification of the deletions in the WAGR region in patients with aniridia should definitely be done. In addition, Wilms tumor can have a very rapid growth, which, per se requires frequent and careful ultrasound kidney controls. Polycystic kidneys can be part of the WAGR presentation.
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PMID:Billateral polycystic kidneys in a girl with WAGR syndrome. 2166 Apr 3

The renal prognosis of patients with Wilms' tumor, aniridia, genitourinary anomalies, and mental retardation syndrome (WAGR) is poor. However, the renal histology and its mechanisms are not well understood. We performed renal biopsies in 3 patients with WAGR syndrome who had heavy proteinuria. The complete deletion of one WT1 allele was detected in each patient by constitutional chromosomal deletion at 11p13 using G-banding, high-resolution G-banding, and fluorescence in situ hybridization. The patients exhibited proteinuria at the ages of 6, 10, and 6 years and were diagnosed as having focal segmental glomerulosclerosis (FSGS) at the ages of 7, 16 and 19 years, respectively. They exhibited normal or mildly declined renal function at the time of biopsy. Re-examination of a nephrectomized kidney from 1 patient revealed that some glomeruli showed segmental sclerosis, although he did not have proteinuria at the time of nephrectomy. The other 2 patients did not develop Wilms' tumor and thus did not undergo nephrectomy, chemotherapy, or radiotherapy, thereby eliminating any effect of these therapies on the renal histology. In conclusion, complete deletion of one WT1 allele may induce the development of FSGS. Our findings suggest that haploinsufficiency of the WT1 could be responsible for the development of FSGS.
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PMID:Focal segmental glomerulosclerosis in patients with complete deletion of one WT1 allele. 2258 69

Individuals who are carriers of deletions of various sizes that cause haploinsufficiency in the contiguous WT1 and PAX6 genes, located on chromosome 11p13 approximately 4 Mb centromeric to the BDNF gene, are susceptible to Wilms tumor, aniridia, mental retardation, genitourinary anomalies and obesity (WAGRO syndrome). The molecular characterization of the wide deletion 11p15.1p12 arr (18676926-36576388) x1 dn in a child with 3 years and 4 months of age only affected by aniridia, predicts not only other serious associated diseases, but also allows us to hypothesize a specific phenotype of mental impairment, conduct alterations and childhood obesity, possibly added to the onset of metabolic alterations. The variable appearance and/or description of haploinsufficiency for obesity susceptibility in the WAGR syndrome mainly depends on the critical region located within 80 kb of exon 1 of BDNF. The relationship between genetic variation based on the genotype combinations of the 4 gene SNPs tagging the BDNF gene and the body mass index (BMI) was studied. The polymorphic variability was similarly distributed in 218 children suffering a severe and non-syndromic obesity from families at high risk for obesity, as compared with 198 controls. The corroborated role of the BDNF gene as highly susceptible to severe syndromic obesity has not already been evidenced in the molecular basis of overweight attributed to the common polygenic principles. Its potential role as risk modifier variant to provoke more severe phenotype has not yet been demonstrated. Some genetic variants of brain-derived neurotrophic factor (BDNF) have resulted in important disorders of energy balance, but it is essential to know exactly their deleterious human capacity because they play a fundamental role in the development and plasticity of the central nervous system in regulating food intake. The existence of polymorphic amino acid changes of unknown functional significance in patients carrying the haploinsufficiency of the BDNF gene could constitute an adequate model to study in depth their effects.
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PMID:The modifier effect of the BDNF gene in the phenotype of the WAGRO syndrome. 2326 38

Wilm's tumour, aniridia, genitourinary abnormalities, and mental retardation (WAGR) syndrome is a rare genetic disorder with an estimated prevalence of 1 in 500,000 to 1 million. It is a contiguous gene syndrome due to deletion at chromosome 11p13 in a region containing WT1 and PAX6 genes. Children with WAGR syndrome mostly present in the newborn/infancy period with sporadic aniridia. The genotypic defects in WAGR syndrome have been well established. However, antenatal ultrasonographic presentation of this syndrome has never been reported. Prenatal diagnosis of this condition is possible in some cases with careful ultrasound examination of classical and nonclassical manifestations of this syndrome. The key point for this rare diagnosis was the decision to perform chromosomal microarray analysis after antenatal diagnosis of absent corpus callosum and absent cavum septum pellucidum, as this finding mandates search for potentially associated genetic disorders. We report a case of WAGR syndrome diagnosed prenatally at 29-week gestation. The diagnosis of the anomaly was based on two- and three-dimensional ultrasound as well as fetal MRI scan and microarray analysis. The ultrasonographic findings included borderline ventriculomegaly, absent corpus callosum, and absent cavum septum pellucidum. Cytogenetic results from the amniotic fluid confirmed WAGR syndrome. Parental karyotype was normal, with no evidence of copy number change, deletion, or rearrangement of this region of chromosome 11.
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PMID:Prenatal Diagnosis of WAGR Syndrome. 2660 98

Mutations in human zinc-finger transcription factor WT1 result in abnormal development of the kidneys and genitalia and an array of pediatric problems including nephropathy, blastoma, gonadal dysgenesis and genital discordance. Several overlapping phenotypes are associated with WT1 mutations, including Wilms tumors, Denys-Drash syndrome (DDS), Frasier syndrome (FS) and WAGR syndrome (Wilms tumor, aniridia, genitourinary malformations, and mental retardation). These conditions vary in severity from individual to individual; they can be fatal in early childhood, or relatively benign into adulthood. DDS mutations cluster predominantly in zinc fingers (ZF) 2 and 3 at the C-terminus of WT1, which together with ZF4 determine the sequence-specificity of DNA binding. We examined three DDS associated mutations in ZF2 of human WT1 where the normal glutamine at position 369 is replaced by arginine (Q369R), lysine (Q369K) or histidine (Q369H). These mutations alter the sequence-specificity of ZF2, we find, changing its affinity for certain bases and certain epigenetic forms of cytosine. X-ray crystallography of the DNA binding domains of normal WT1, Q369R and Q369H in complex with preferred sequences revealed the molecular interactions responsible for these affinity changes. DDS is inherited in an autosomal dominant fashion, implying a gain of function by mutant WT1 proteins. This gain, we speculate, might derive from the ability of the mutant proteins to sequester WT1 into unproductive oligomers, or to erroneously bind to variant target sequences.
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PMID:Denys-Drash syndrome associated WT1 glutamine 369 mutants have altered sequence-preferences and altered responses to epigenetic modifications. 2759 98

Wilm's tumor, aniridia, genitourinary anomalies, and mental retardation (WAGR) syndrome, a rare genetic disorder, is caused by the loss of 11p13 region including PAX6 and WT1. We report novel findings in a 28-month-old boy with aniridia, Wilm's tumor, congenital hypothyroidism, and sublingual thyroid ectopia. He was found to have a mosaic 5.28 Mb interstitial deletion of chromosome 11p13 deleting PAX6 and WT1. In order to clarify the mechanism underlying his thyroid dysgenesis, sequence analysis of candidate thyroid developmental genes was performed. We identified a FOXE1: c.532_537delGCCGCC p.(Ala178_Ala179del) variant that predisposes to thyroid ectopia. Taken together, this is the first report of mosaic 11p13 deletion in association with thyroid dysgenesis. We also propose a model of complex interactions of different genetic variants for this particular phenotype in the present patient.
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PMID:WAGR syndrome and congenital hypothyroidism in a child with a Mosaic 11p13 deletion. 2839 7


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