Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0917816 (mental retardation)
 15,867 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Epilepsy and mental retardation limited to females (EFMR) is a disorder with an X-linked mode of inheritance and an unusual expression pattern. Disorders arising from mutations on the X chromosome are typically characterized by affected males and unaffected carrier females. In contrast, EFMR spares transmitting males and affects only carrier females. Aided by systematic resequencing of 737 X chromosome genes, we identified different protocadherin 19 (PCDH19) gene mutations in seven families with EFMR. Five mutations resulted in the introduction of a premature termination codon. Study of two of these demonstrated nonsense-mediated decay of PCDH19 mRNA. The two missense mutations were predicted to affect adhesiveness of PCDH19 through impaired calcium binding. PCDH19 is expressed in developing brains of human and mouse and is the first member of the cadherin superfamily to be directly implicated in epilepsy or mental retardation.
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PMID:X-linked protocadherin 19 mutations cause female-limited epilepsy and cognitive impairment. 1947 81

Epilepsy and Mental Retardation Limited to Females (EFMR) [OMIM 300088] was first described in 1971 [Juberg and Hellman, 1971] in 15 related females with early onset grand mal seizures and mental retardation. Although EFMR demonstrates X-linked inheritance, it follows an unusual pattern by sparing transmitting males and affecting only heterozygous females. In 2008, mutations within the protocadherin 19 (PCDH19) gene were implicated as causative of EFMR [Dibbens et al. (2008); Nat Genet 40:776-781]. The EFMR phenotype is typically characterized by seizure onset in infancy and mild to severe intellectual impairment. Several individuals with EFMR have also been described as having autistic features. We describe three unrelated female individuals, ranging in age from 3 to 19 years, with de novo novel PCDH19 mutations. All three individuals have seizure onset in infancy and require the use of multiple antiepileptic drugs. They also have varying degrees of intellectual impairment along with the presence of autistic features. Although most individuals with EFMR described to date demonstrate this unusual familial X-linked inheritance, our three unrelated females with de novo mutations highlight the importance of testing PCDH19 in females with early onset epilepsy, intellectual impairment, and autistic features, regardless of family history.
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PMID:Novel de novo PCDH19 mutations in three unrelated females with epilepsy female restricted mental retardation syndrome. 2083 Jul 98

Recently, missense and truncating mutations in the gene PCDH19 have been reported to cause female-restricted epilepsy with mental retardation (EFMR). EFMR (MIM#300088) is an X-linked disorder characterized by early onset seizures and intellectual disability (ID). Interestingly, unlike typical X-linked mode of inheritance, the phenotype is restricted to females, and males are unaffected carriers. PCDH19 is highly expressed in brain, and the encoded protein belongs to the cadherin superfamily. Here we report two unrelated female patients with deletions spanning PCDH19 identified by copy number variation (CNV) analysis and validated by qPCR. In one, we have identified a 3 Mb interstitial deletion at Xq21.33-q22.1 which spans PCDH19, LOC442459 & TNMD. This patient had her first seizure at 8 months old, and also has ID and aggressive behavior. In another female patient we identified a de novo 603 kb heterozygous deletion in a female patient with fits (since 1 year of age), ID, hyperactivity and aggressive behavior. The deletion spans the entire PCDH19 gene (also TNMD, SRPX2, TSPAN6 and SYTL4). In conclusion, our results suggest that deletions at PCDH19 also cause EFMR.
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PMID:Identification of genomic deletions spanning the PCDH19 gene in two unrelated girls with intellectual disability and seizures. 2209 64

Epilepsy and mental retardation limited to females (EFMR) is a genetic disorder that affects females but spares transmitting males. The condition is caused by protocadherin 19 mutations and is characterised by seizures beginning at around 1 year of age, frequently associated with cognitive regression at seizure onset or later. Seizures can be generalised or focal, exacerbated by febrile illnesses, and grouped in clusters. This report shows the first video-EEG recording of EFMR, in a 7-year-old female presenting peculiar ictal features. [Published with video sequences].
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PMID:Semiological study of ictal affective behaviour in epilepsy and mental retardation limited to females (EFMR). 2293 93

The occurrence of epilepsy with mental retardation limited to females (EFMR; MIM 300088) has been recently associated to mutations in the PCDH19 gene, located on chromosome X and encoding for protocadherin 19. EFMR shows a rare X-linked inheritance wherein affected females may be segregating a mutation through unaffected transmitting males (Fabisiak and Erickson Clin Genet 38(5):353-358, 1990; Juberg and Hellman J Pediatr 79:726-732, 1971; Ryan et al. Nat Genet 17(1):92-95, 1997). The description of a pedigree segregating PCDH19 mutations from unaffected mothers to patients (Depienne et al. Hum Mutat 32:E1959-1975, 2011; Dibbens et al. Neurology 76:1514-1519, 2011) complicates disease inheritance and genetic counseling. In the present study, we describe a PCDH19 mutation segregating from an asymptomatic mother to an EFMR patient. In order to correlate the healthy phenotype with the genotype of the transmitting mother, we quantified in a few tissues the level of the mutant allele by real-time PCR, disclosing a somatic mosaicism. This finding has a great impact on genetic counseling.
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PMID:Somatic mosaicism of PCDH19 mutation in a family with low-penetrance EFMR. 2294 44

Epilepsy and mental retardation limited to females (EFMR), caused by PCDH19 mutations, has a variable clinical expression that needs further exploration. Onset of epilepsy may be provoked by fever and can resemble Dravet syndrome. Furthermore, transmitting males have no seizures, but are reported to have rigid personalities suggesting possible autism spectrum disorders (ASD). Therefore, this study aimed to determine the phenotypic spectrum associated with PCDH19 mutations in Dravet-like and EFMR female patients and in males with ASD. We screened 120 females suffering from Dravet-like epilepsy, 136 females with EFMR features and 20 males with ASD. Phenotypes and genotypes of the PCDH19 mutation carriers were compared with those of 125 females with EFMR reported in the literature. We report 15 additional patients with a PCDH19 mutation. Review of clinical data of all reported patients showed that the clinical picture of EFMR is heterogeneous, but epilepsy onset in infancy, fever sensitivity and occurrence of seizures in clusters are key features. Seizures remit in the majority of patients during teenage years. Intellectual disability and behavioural disturbances are common. Fifty percent of all mutations are missense mutations, located in the extracellular domains only. Truncating mutations have been identified in all protein domains. One ASD proband carried one missense mutation predicted to have a deleterious effect, suggesting that ASD in males can be associated with PCDH19 mutations.
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PMID:Clinical and genetic aspects of PCDH19-related epilepsy syndromes and the possible role of PCDH19 mutations in males with autism spectrum disorders. 2333 64

Protocadherin 19 (PCDH19) female limited epilepsy (PCDH19-FE; also known as epilepsy and mental retardation limited to females, EFMR; MIM300088) is an infantile onset epilepsy syndrome with or without intellectual disability (ID) and autism. We investigated transcriptomes of PCDH19-FE female and control primary skin fibroblasts, which are endowed to metabolize neurosteroid hormones. We identified a set of 94 significantly dysregulated genes in PCDH19-FE females. Intriguingly, 43 of the 94 genes (45.7%) showed gender-biased expression; enrichment of such genes was highly significant (P = 2.51E-47, two-tailed Fisher exact test). We further investigated the AKR1C1-3 genes, which encode crucial steroid hormone-metabolizing enzymes whose key products include allopregnanolone and estradiol. Both mRNA and protein levels of AKR1C3 were significantly decreased in PCDH19-FE patients. In agreement with this, the blood levels of allopregnanolone were also (P < 0.01) reduced. In conclusion, we show that the deficiency of neurosteroid allopregnanolone, one of the most potent GABA receptor modulators, may contribute to PCDH19-FE. Overall our findings provide evidence for a role of neurosteroids in epilepsy, ID and autism and create realistic opportunities for targeted therapeutic interventions.
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PMID:Mutations of protocadherin 19 in female epilepsy (PCDH19-FE) lead to allopregnanolone deficiency. 2612 93