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)

Epilepsy rarely occurs in patients with hereditary spastic paraplegia (HSP), and is not included in the description of the 'complicated' form of HSP by Harding. We report 3 patients with HSP in a family of two generations. Two of them also had epilepsy, mental retardation and hearing impairment. The disorder was inherited as an autosomal dominant trait.
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PMID:Hereditary spastic paraplegia associated with epilepsy, mental retardation and hearing impairment. 833 6

The most common inherited form of hydrocephalus, X linked hydrocephalus (HSAS), is characterised by mental retardation, adducted thumbs, and spastic paraplegia. Genetic analysis has mapped the locus for HSAS to subchromosomal band Xq28 within a region of approximately 2 megabases of DNA. In order to refine the location of the disease gene we have conducted genetic linkage analysis with Xq28 marker loci in four additional HSAS families. A lod score of 4.26 with polymorphic marker DXS52 (St14) confirms the linkage of HSAS to Xq28. Identification of a recombination event between the HSAS gene and Xq28 loci F8C and DXS605 (2-19) reduces the size of the interval likely to contain the disease locus to about 1.5 megabases, the distance between DXS605 and DXS52. The locus for neural cell adhesion molecule, L1CAM, maps within this interval and therefore represents a candidate gene for HSAS.
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PMID:Refining the genetic location of the gene for X linked hydrocephalus within Xq28. 847 7

L1 is a neuronal cell adhesion molecule with important functions in the development of the nervous system. The gene encoding L1 is located near the telomere of the long arm of the X chromosome in Xq28. We review here the evidence that several X-linked mental retardation syndromes including X-linked hydrocephalus (HSAS), MASA syndrome, X-linked complicated spastic paraparesis (SP1) and X-linked corpus callosum agenesis (ACC) are all due to mutations in the L1 gene. The inter- and intrafamilial variability in families with an L1 mutation is very wide, and patients with HSAS, MASA, SP1 and ACC can be present within the same family. Therefore, we propose here to refer to this clinical syndrome with the acronym CRASH, for Corpus callosum hypoplasia, Retardation, Adducted thumbs, Spastic paraplegia and Hydrocephalus.
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PMID:CRASH syndrome: clinical spectrum of corpus callosum hypoplasia, retardation, adducted thumbs, spastic paraparesis and hydrocephalus due to mutations in one single gene, L1. 855 2

We report on clinical and cytogenetic data on 5 children and 2 adults with a de novo inverted duplication of the short arm of chromosome 8, and we give a review of 26 patients from the literature. The clinical picture in young children is characterized by minor facial anomalies, hypotonia, and severe developmental delay. In older patients the facial traits are less characteristic, spastic paraplegia develops, and severe orthopedic problems are frequent. Psychomotor retardation is always severe-to-profound. Duplication of 8p21-p22 results in a clinically recognizable multiple congenital anomalies/mental retardation (MCA/MR) syndrome. It is shown that in all patients examined, the duplication was accompanied by a deletion of the most terminal part of 8p.
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PMID:Inversion duplication of the short arm of chromosome 8: clinical data on seven patients and review of the literature. 859 64

Two patients with X-chromosomal hydrocephalus internus (aqueduct stenosis, clasped thumbs, mental retardation and spasticity) habe been described. In both cases the family history revealed further affected relatives. The intra- and interfamilial variability of this rare X-chromosomal recessive disease will be demonstrated. In this context differentialdiagnoses like X-linked MASA syndrome and X-linked spastic paraplegia have been discussed on the basis of a variable expressivity of different mutations in the same gene.
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PMID:[X-chromosomal recessive hydrocephalus internus: a separate disease picture? 2 further case reports and review of the literature]. 867 3

Autosomal dominant, autosomal recessive and X-linked recessive varieties of spastic paraplegia have been recognized. Recently, Japanese patients with complicated form of autosomal recessive hereditary spastic paraplegia (HSP) associated with hypoplasia of the corpus callosum have been reported by Iwabuchi et al. We describe a patient with complicated HSP (Iwabuchi type) and cataracta. A 38-year-old man (his parents were a second cousin) was born uneventfully. His motor development was normal. Motor and mental dysfunctions were noticed during the lower classes of an elementary school. He could ride a bicycle at 18 years old but gradually developed galt disturbance and confined to wheelchair since 35 years. He was admitted to our hospital on February 25, 1994. A neurological examination showed mental retardation, dementia, cataracta, cerebellar ataxia, rigidity, spasticity, severe atrophy of the distal muscles of his extremities, paraparesis, hyperreflexia, positive Hoffmann reflexes and Babinski signs, pes cavus and hammer toes. Brain MRI showed thinning of corpus callosum. Clinical and laboratory findings did not support a diagnosis of metabolic disorders showing spastic paraparesis including adrenomyeloneuropathy, Globoid leukodystrophy, metachromatic leukodystrophy, cerebrotendinous xanthomatosis, Arginase deficiency. We considered that our patient was complicated form of HSP (Iwabuchi et al). However, cataract has not been found in Iwabuchi type of HSP. We discussed here other reports showing cataracta with spastic paraparesis.
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PMID:[A case of complicated form of hereditary spastic paraplegia associated with hypoplasia of the corpus callosum and cataracta]. 877 6

X-linked hereditary spastic paraplegias (HSP) present with two distinct phenotypes, pure and complicated. The pure form is characterized by spasticity and gait difficulties but lacks the additional features (nystagmus, dysarthria, mental retardation) present in the complicated form. The complicated form is heterogeneous, caused by mutations of the L1CAM gene at Xq28 (SPG1) or the PLP gene at Xq22 (SPG2) that is allelic to Pelizaeus-Merzbacher disease (PMD). Since in one kindred (K313) the pure form of HSP was also mapped to Xq22, this raises the issue as to whether a pure form of HSP exists that is allelic to X-linked complicated HSP (SPG2) and PMD. To answer this question, we carried out linkage analysis in a new pedigree with pure HSP (K101) and refined linkage in pedigree K313. The PLP gene was also screened for mutation by direct sequencing and reverse-transcriptase polymerase chain reaction (RT-PCR). In both families, the disease locus mapped to Xq22 with Lod scores at zero recombination of 5.3 for COL4A5 2B6 in K313 and 2.4 for DXS101 in K101. A T to C transition in exon 5 of the PLP gene was identified from affected individuals of K313. This transition causes a Ser to Pro mutation in the major extracellular loop of PLP/DM20. This finding demonstrates that a form of X-linked pure spastic paraplegia, X-linked complicated HSP (SPG2) and PMD are allelic disorders. There was no evidence of mutations in either coding sequences or the intron/exon junctions of PLP in pedigree K101, suggesting that the disease-producing mutation may be in the noncoding portions of PLP or in a nearby gene.
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PMID:Refined genetic mapping and proteolipid protein mutation analysis in X-linked pure hereditary spastic paraplegia. 878 Jan 1

Familial spastic paraplegia (FSP or SPG) is a genetically heterogeneous group of upper motor neuron syndromes. To date, two distinct loci for X-linked recessive type (SPG1 and SPG2), three loci for autosomal dominant type (FSP1, FSP2 and FSP3), and one locus for autosomal recessive type have been reported. SPG1 and SPG2 have been mapped to Xq28 and Xq21-q22, respectively. SPG1 shows a mutation in the gene for neural cell adhesion molecule L1 (LICAM), which is an axonal glycoprotein involved in neuronal migration and differentiation. Different mutations of the same L1 gene also cause. MASA (mental retardation, aphasia, spastic paraplegia, adducted thumbs) syndrome and X-linked hydrocephalus. SPG2 shows mutations in one of the major myelin proteins, the proteolipid protein (PLP) gene, and is allelic to Pelizaeus-Merzbacher disease. Thus, mutations in two functionally distinct genes manifest the phenotype of X-linked spastic paraparesis. Three dominantly inherited spastic paraplegia genes have been genetically mapped to regions of chromosomes, yet no specific genes or mutations have been identified. FSP1 is mapped to a region of 7 cM on chromosome 14q12-q23 (approximately 20% of dominant FSP families) and FSP2 to 4 cM on chromosome 2p21-p24 (approximately 70% of dominant FSP families). Anticipation (increasing clinical severity in successive generations) has been observed in both FSP1 and FSP2 families. Another autosomal dominant FSP (FSP3) has been mapped in the centromeric region of chromosome 15q (< 10% of dominant FSP families). An autosomal recessive FSP has been mapped to chromosome 8q. The definite genetic heterogeneity in FSP indicates that a multitude of genes/proteins can cause spastic paraplegia. Clinical features of each of the loci which may permit differential diagnosis are discussed. We also present pedigrees of two new FSP families.
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PMID:Molecular genetics of familial spastic paraplegia: a multitude of responsible genes. 878 67

X-linked hydrocephalus (HSAS) is the most common form of inherited hydrocephalus characterized by hydrocephalus due to stenosis of the aqueduct of Sylvius, mental retardation, clasped thumbs, and spastic paraparesis. MASA syndrome (mental retardation, aphasia, shuffling gait and adducted thumbs) and SPG1 (X-linked complicated spastic paraplegia) are also X-linked disorders with overlapping clinical signs. Linkage analysis studies implicated the neural cell adhesion molecule L1 (L1CAM) gene as a candidate gene for these X-linked disorders. This genetic study analyzes the L1CAM gene in a Japanese family with members suffering from HSAS, and describes a deletion of five nucleotides in exon 8. Screening by Bg1I digestion of polymerase chain reaction (PCR) products revealed that two siblings have the same mutation and a sister was identified as a heterozygous carrier. The 5 nucleotide deletion causes a shift of the reading frame and introduces a premature stop codon 72 nucleotides downstream, which might result in a truncated protein. The mutation identified herein is a novel L1CAM mutation, which triggers hydrocephalus. We report a unique L1CAM mutation that causes HSAS: the first report of such a mutation in a Japanese family.
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PMID:A deletion of five nucleotides in the L1CAM gene in a Japanese family with X-linked hydrocephalus. 878 80

Mutations in the gene encoding the neuronal cell adhesion molecule L1 are responsible for several syndromes with clinical overlap, including X-linked hydrocephalus (XLH, HSAS), MASA (mental retardation, aphasias, shuffling gait, adducted thumbs) syndrome, complicated X-linked spastic paraplegia (SP 1), X-linked mental retardation-clasped thumb (MR-CT) syndrome, and some forms of X-linked agenesis of the corpus callosum (ACC). We review 34 L1 mutations in patients with these phenotypes.
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PMID:The clinical spectrum of mutations in L1, a neuronal cell adhesion molecule. 882 52


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