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)

Hirschsprung disease, mental retardation, microcephaly, and specific craniofacial dysmorphism were observed in three children from a large, consanguineous, Moroccan family. A fourth child showed similar clinical features, with the exception of Hirschsprung disease. The association of these abnormalities in these children represents the Goldberg-Shprintzen syndrome (OMIM 235730). Mutation scanning of genes potentially involved in Hirschsprung disease, RET, GDNF, EDN3, and EDNRB, showed a sequence variant, Ser305Asn, in exon 4 of the EDNRB gene in the index patient of this family. The Ser305Asn substitution present in two of the four patients and four healthy relatives and absent in one of the remaining two patients illustrates the difficulties in interpreting the presence of mutations in families with Hirschsprung disease. It is unlikely that the EDNRB variant contributes to the phenotype. This consanguineous family might be useful for the identification of a Goldberg-Shprintzen locus.
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PMID:A consanguineous family with Hirschsprung disease, microcephaly, and mental retardation (Goldberg-Shprintzen syndrome). 1087 40

Hirschsprung's disease occurs rarely and sporadically in adult, involving males. In cases, which are manifested perinatally, the so called Hirschsprung-associated congenital anomalies (mainly central nervous system, urogenital and cardiovascular) may present (2-21%), which have not observed in adult. Mental retardation and Hirschsprung's disease more frequently are associated with Down syndrome (5-10%). The discoveries of molecular genetics in the last 4-5-years through the examination of transgenic ("knockout") mice, proved the basic role the mutation of 4 genes: the RET (receptor tyrosin kinase), a proto-oncogene, coding its ligand, the glial cell-line derived neutrophic factor (GDNF), the gene of the endothelin-B receptor (ENDRB) and the gene one of its ligand, the endothelin-3 (EDN3), in the pathogenesis of Hirschsprung's disease. In our case, the short segment Hirschsprung's disease caused respiratory and cardiac failure, which was recognized by autopsy. Besides, the severe mental retardation, the role of the long term use of antipsychotic medicines comes up in the prolongation and masking of the symptoms. The accompanied mental retardation and microcephalia in early childhood are known, which are associated anomalies with Hirschsprung's disease. In cases of Hirschsprung diseases at adults, no other associated congenital anomalies has been published. The mental retardation in Down-syndrome, in association with Hirschsprung's disease (and presumable in our case, too) is supposed to be the consequence of the mutation in the gene of GDNF. In this case, we observed, that the so called short segment H-d was accompanied at a 33 years old men patient with mental retardation (who was originated from a gypsy ethnic minority), because of it the connection of the nurses and the patient was disturbed and the main symptom of the H-d (chronic obstipation) remained hidden. The mechanic ileus was going on behind the scenes, and in addition to the cardiac failure caused the death of the patient. Practical conclusion of the case is that, Hirschsprung's disease should be suspected in all adult patients, who had severe obstipation persisting since childhood, especially in males.
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PMID:[Adult Hirschsprung's disease with mental retardation and microcephaly]. 1096 5

Hirschsprung disease (HSCR) stands as a model for genetic dissection of complex diseases. In this model, a major gene, RET, is involved in most if not all cases of isolated (i.e., nonsyndromic) HSCR, in conjunction with other autosomal susceptibility loci under a multiplicative model. HSCR susceptibility alleles can harbor either heterozygous coding sequence mutations or, more frequently, a polymorphism within intron 1, leading to a hypomorphic RET allele. On the other hand, about 30% of HSCR are syndromic. Hitherto, the disease causing gene has been identified for eight Mendelian syndromes with HSCR: congenital central hypoventilation (CCHS), Mowat-Wilson (MWS), Bardet-Biedl (BBS), Shah-Waardenburg (WS4), cartilage-hair-hypoplasia (CHH), Smith-Lemli-Opitz (SLO), Goldberg-Sprintzsen (GSS), and hydrocephalus due to congenital stenosis of the aqueduct of sylvius (HSAS). According to the HSCR syndrome, the penetrance of HSCR trait varies from 5 to 70%. Trisomy 21 (T21) also predisposes to HSCR. We were able to collect a series of 393 patients affected by CCHS (n = 173), WS4 (n = 24), BBS (n = 51), MWS (n = 71), T21 (n = 46), and mental retardation (MR) with HSCR (n = 28). For each syndrome, we studied the RET locus in two subgroups of patients; i.e., with or without HSCR. We genotyped the RET locus in 393 patients among whom 195 had HSCR, and compared the distribution of alleles and genotypes within the two groups for each syndrome. RET acts as a modifier gene for the HSCR phenotype in patients with CCHS, BBS, and Down syndrome, but not in patients with MWS and WS4. The frequent, low penetrant, predisposing allele of the RET gene can be regarded as a risk factor for the HSCR phenotype in CCHS, BBS, and Down syndrome, while its role is not significant in MWS and WS4. These data highlight the pivotal role of the RET gene in both isolated and syndromic HSCR.
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PMID:Epistatic interactions with a common hypomorphic RET allele in syndromic Hirschsprung disease. 1739 38

Pitt-Hopkins syndrome is a rarely reported syndrome of so-far-unknown etiology characterized by mental retardation, wide mouth, and intermittent hyperventilation. By molecular karyotyping with GeneChip Human Mapping 100K SNP arrays, we detected a 1.2-Mb deletion on 18q21.2 in one patient. Sequencing of the TCF4 transcription factor gene, which is contained in the deletion region, in 30 patients with significant phenotypic overlap revealed heterozygous stop, splice, and missense mutations in five further patients with severe mental retardation and remarkable facial resemblance. Thus, we establish the Pitt-Hopkins syndrome as a distinct but probably heterogeneous entity caused by autosomal dominant de novo mutations in TCF4. Because of its phenotypic overlap, Pitt-Hopkins syndrome evolves as an important differential diagnosis to Angelman and Rett syndromes. Both null and missense mutations impaired the interaction of TCF4 with ASCL1 from the PHOX-RET pathway in transactivating an E box-containing reporter construct; therefore, hyperventilation and Hirschsprung disease in patients with Pitt-Hopkins syndrome might be explained by altered development of noradrenergic derivatives.
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PMID:Haploinsufficiency of TCF4 causes syndromal mental retardation with intermittent hyperventilation (Pitt-Hopkins syndrome). 1743 55