Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0026838 (spasticity)
 6,471 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The aim of the study was to enhance our understanding of the pathogenesis of the ataxia of Charlevoix-Saguenay, based on the findings presented herein. Five patients with a molecular diagnosis of this disease underwent clinical, radiological, ophthalmologic and electrophysiological examinations. Five novel mutations, which included nonsense and missense variants, were identified, with these resulting in milder phenotypes. In addition to the usual manifestations, a straight dorsal spine was found in every case, and imaging techniques showed loss of the dorsal kyphosis. Cranial MRI demonstrated hypointense linear striations at the pons. Tensor diffusion MRI sequences revealed that these striations corresponded with hyperplastic pontocerebellar fibres, and tractographic sequences showed interrupted pyramidal tracts at the pons. Ocular coherence tomography demonstrated abnormal thickness of the nerve fibre layer. Electrophysiological studies showed nerve conduction abnormalities compatible with a dysmyelinating neuropathy, with signs of chronic denervation in distal muscles. The authors suggest that the hyperplastic pontocerebellar fibres compress the pyramidal tracts at the pons, and that the amount of retinal fibres traversing the optic discs is enlarged. These facts point to the contribution of an abnormal developmental mechanism in the ataxia of Charlevoix-Saguenay. Accordingly, spasticity would be mediated by compression of the pyramidal tracts, neuromuscular symptoms by secondary axonal degeneration superimposed on the peripheral myelinopathy, while the cause of the progressive ataxia remains speculative. The distinctive aspect of the dorsal spine could be of help in the clinical diagnosis.
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PMID:New findings in the ataxia of Charlevoix-Saguenay. 2199 19

We report an early onset spastic ataxia-neuropathy syndrome in two brothers of a consanguineous family characterized clinically by lower extremity spasticity, peripheral neuropathy, ptosis, oculomotor apraxia, dystonia, cerebellar atrophy, and progressive myoclonic epilepsy. Whole-exome sequencing identified a homozygous missense mutation (c.1847G>A; p.Y616C) in AFG3L2, encoding a subunit of an m-AAA protease. m-AAA proteases reside in the mitochondrial inner membrane and are responsible for removal of damaged or misfolded proteins and proteolytic activation of essential mitochondrial proteins. AFG3L2 forms either a homo-oligomeric isoenzyme or a hetero-oligomeric complex with paraplegin, a homologous protein mutated in hereditary spastic paraplegia type 7 (SPG7). Heterozygous loss-of-function mutations in AFG3L2 cause autosomal-dominant spinocerebellar ataxia type 28 (SCA28), a disorder whose phenotype is strikingly different from that of our patients. As defined in yeast complementation assays, the AFG3L2(Y616C) gene product is a hypomorphic variant that exhibited oligomerization defects in yeast as well as in patient fibroblasts. Specifically, the formation of AFG3L2(Y616C) complexes was impaired, both with itself and to a greater extent with paraplegin. This produced an early-onset clinical syndrome that combines the severe phenotypes of SPG7 and SCA28, in additional to other "mitochondrial" features such as oculomotor apraxia, extrapyramidal dysfunction, and myoclonic epilepsy. These findings expand the phenotype associated with AFG3L2 mutations and suggest that AFG3L2-related disease should be considered in the differential diagnosis of spastic ataxias.
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PMID:Whole-exome sequencing identifies homozygous AFG3L2 mutations in a spastic ataxia-neuropathy syndrome linked to mitochondrial m-AAA proteases. 2202 84

The Japan Spastic Paraplegia Research Consortium (JASPAC) is conducting a nationwide clinical and genetic survey of patients with HSP in Japan. To date (July 20, 2011), 375 index patients with HSP from 42 prefectures in Japan have been registered. In 148 Japanese ADHSP families, SPG4 was the most common form, accounting for 47%, followed by SPG31 (4%), SPG3A (3%), SPG8 (1%), and SPG10 (1%). Meanwhile, preliminary data showed that SPG11 and ARSACS were common in Japanese ARHSP families. Since the genes in approximately 40% of ADHSP and 80% of ARHSP cases remain unknown, we aim to identify the new genes responsible for HSP. We are now searching for a novel gene responsible for ARHSP with optic atrophy and neuropathy. To date, non-Quebec patients with ARSACS have been found in the Mediterranean area, Europe and Japan. Although Quebec patients show a homogeneous phenotype, Japanese patients exhibit some atypical clinical features, as follows: slightly later onset than that in Quebec patients, absence of retinal hypermyelination, intellectual impairment, and lack of spasticity. Recently, we found characteristic MRI findings in eight Japanese ARSACS patients, who all exhibited linear hypointensity in the pons and a hypointense area in the middle cerebellar peduncles in T(2) weighted and FLAIR images.
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PMID:[Hereditary spastic paraplegia in Japan]. 2227 6

Autosomal recessive spastic ataxia of Charlevoix-Saguenay (ARSACS) is an inherited neurodegenerative disorder with symptoms of spastic ataxia, neuropathy, pyramidal sign, finger and foot deformities, and hypermyelination of retinal nerve fibers. SACS is mutated in ARSACS. The clinical diversity of ARSACS is recognized, which sometimes makes its diagnosis difficult. By using homozygosity mapping, we identified a novel homozygous c.12020C > T missense mutation in a consanguineous Japanese family with atypical clinical features. In addition to the absence of spasticity and hypermyelinated retinal nerve fibers, the present case had urinary dysfunction, impotence, and severe constipation, indicating the possibility of autonomic dysfunction. Furthermore, we showed the diagnostic usefulness of MRI even for the case of atypical clinical features. It had been considered that cases without obvious spasticity were very rare, however recent reports on atypical cases as well as our case indicate that ARSACS cases without obvious spasticity might be more frequent than previously thought. We should be aware of atypical features of ARSACS for the correct diagnosis.
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PMID:A novel SACS mutation in an atypical case with autosomal recessive spastic ataxia of Charlevoix-Saguenay (ARSACS). 2289 8

Mutations in the spastic paraplegia 7 (SPG7) gene encoding paraplegin are responsible for autosomal recessive hereditary spasticity. We screened 135 unrelated index cases, selected in five different settings: SPG7-positive patients detected during SPG31 analysis using SPG31/SPG7 multiplex ligation-dependent probe amplification (n = 7); previously reported ambiguous SPG7 cases (n = 5); patients carefully selected on the basis of their phenotype (spasticity of the lower limbs with cerebellar signs and/or cerebellar atrophy on magnetic resonance imaging/computer tomography scan and/or optic neuropathy and without other signs) (n = 24); patients with hereditary spastic paraparesis referred consecutively from attending neurologists and the national reference centre in a diagnostic setting (n = 98); and the index case of a four-generation family with autosomal dominant optic neuropathy but no spasticity linked to the SPG7 locus. We identified two SPG7 mutations in 23/134 spastic patients, 21% of the patients selected according to phenotype but only 8% of those referred directly. Our results confirm the pathogenicity of Ala510Val, which was the most frequent mutation in our series (65%) and segregated at the homozygous state with spastic paraparesis in a large family with autosomal recessive inheritance. All SPG7-positive patients tested had optic neuropathy or abnormalities revealed by optical coherence tomography, indicating that abnormalities in optical coherence tomography could be a clinical biomarker for SPG7 testing. In addition, the presence of late-onset very slowly progressive spastic gait (median age 39 years, range 18-52 years) associated with cerebellar ataxia (39%) or cerebellar atrophy (47%) constitute, with abnormal optical coherence tomography, key features pointing towards SPG7-testing. Interestingly, three relatives of patients with heterozygote SPG7 mutations had cerebellar signs and atrophy, or peripheral neuropathy, but no spasticity of the lower limbs, suggesting that SPG7 mutations at the heterozygous state might predispose to late-onset neurodegenerative disorders, mimicking autosomal dominant inheritance. Finally, a novel missense SPG7 mutation at the heterozygous state (Asp411Ala) was identified as the cause of autosomal dominant optic neuropathy in a large family, indicating that some SPG7 mutations can occasionally be dominantly inherited and be an uncommon cause of isolated optic neuropathy. Altogether, these results emphasize the clinical variability associated with SPG7 mutations, ranging from optic neuropathy to spastic paraplegia, and support the view that SPG7 screening should be carried out in both conditions.
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PMID:Spastic paraplegia gene 7 in patients with spasticity and/or optic neuropathy. 2306 89

In patients with Charcot spine, a loss of normal feedback response from the insensate spine results in spinal neuropathy. Increasing deformity, which can manifest as sitting imbalance, crepitus, or increased back pain, can result. We present the case of a patient with a high-thoracic spinal cord injury (SCI) who subsequently developed a Charcot joint at the T10-11 level that resulted in a dramatic increase in previously controlled spasticity after fracture of an existing baclofen catheter. The 68-year-old man with T4 paraplegia presented with increasing baclofen requirements and radiographic evidence of fracture of the intrathecal baclofen catheter with an associated Charcot joint with extensive bony destruction. The neuropathic spinal arthropathy caused mechanical baclofen catheter malfunction and resulting increased spasticity. The patient was found to have transected both his spinal cord and the baclofen catheter. Treatment consisted of removal of the catheter and stabilization with long-segment instrumentation and fusion from T6 to L2. Follow-up radiographs obtained a year and a half after surgery showed no evidence of hardware failure or significant malalignment. The patient has experienced resolution of symptoms and does not require oral or intrathecal baclofen. This is the only reported case of a Charcot spine causing intrathecal catheter fracture, leading to increased spasticity. This noteworthy case suggests that late spinal instability should be considered in the setting of SCI and increased spasticity.
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PMID:Increased spasticity from a fracture in the baclofen catheter caused by Charcot spine: case report. 2546 26

Silver syndrome/spastic paraplegia 17 is an autosomal dominant, complicated hereditary spastic paraparesis in which spasticity of the legs is accompanied by amyotrophy of the hands and occasionally also the lower limbs. Heterozygous mutations of its causative gene, the Berardinelli-Seip congenital lipodystrophy gene, have a broader spectrum of phenotypes including Silver syndrome, distal hereditary motor neuropathy type V and Charcot-Marie-Tooth disease type 2. We report a Chinese family carrying the S90L mutation with Silver syndrome and discuss our literature review of the clinical phenotypes of S90L. Most reported patients (21 of 26) with this mutation showed a phenotype of Silver syndrome. The S90L mutation is predominantly associated with Silver syndrome.
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PMID:BSCL2 S90L mutation in a Chinese family with Silver syndrome with a review of the literature. 2548 75

Hereditary spastic paraplegias (HSPs) were characterized by progressive leg spasticity with various additional symptoms as follows: peripheral neuropathy, cerebellar ataxia, extrapyramidal symptoms, mental impairment, optic atrophy, pigmental retinopathy, and so on. Many genetic loci (SPG1-72) and more than 50 genes were identified so far. Recently, we identified the causative gene, C12orf65, that was reported the gene for Leigh syndrome, for autosomal recessive spastic paraplegia with optic atrophy and neuropathy (SPG55). We also identified the mutation of the LYST gene, that is causative gene for Chediak-Higashi syndrome, for the autosomal recessive complicated spastic paraplegia with cerebellar ataxia and neuropathy. In this review, we introduced clinical symptoms about our cases suffered from SPG4, SPG11, SPG55 and complicated spastic paraplegia due to adult Chediak-Higashi syndrome. SPG4, that is usually exhibits pure spastic paraplegia, but our case shows mental impairment and variable age of onset. HSPs are clinically and genetically heterogeneous syndromes, i. e., same gene mutations with different clinical manifestations or same clinical presentations with different gene mutations. We should perform board range differential diagnosis and analysis of numerous causative genes to the patients with spastic paraplegia, especially autosomal recessive trait.
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PMID:[Clinical aspects of hereditary spastic paraplegias]. 2551 61

To identify novel mutations causing hereditary motor and sensory neuropathy (HMSN) with pyramidal signs, a variant of Charcot-Marie-Tooth disease (CMT), we screened 28 CMT and related genes in four members of an affected Japanese family. Clinical features included weakness of distal lower limb muscles, foot deformity, and mild sensory loss, then late onset of progressive spasticity. Electrophysiological studies revealed widespread neuropathy. Electron microscopic analysis showed abnormal mitochondria and mitochondrial accumulation in the neurons and Schwann cells. Brain magnetic resonance imaging (MRI) revealed an abnormally thin corpus callosum. In all four, microarrays detected a novel heterozygous missense mutation c.1166A>G (p.Y389C) in the gene encoding the light-chain neurofilament protein (NEFL), indicating that NEFL mutations can result in a HMSN with pyramidal signs phenotype.
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PMID:Neurofilament light mutation causes hereditary motor and sensory neuropathy with pyramidal signs. 2558 83

Hereditary Spastic Paraplegia (HSP) is a syndrome characterised by lower limb spasticity, occurring alone or in association with other neurological manifestations, such as cognitive impairment, seizures, ataxia or neuropathy. HSP occurs worldwide, with different populations having different frequencies of causative genes. The Greek population has not yet been characterised. The purpose of this study was to describe the clinical presentation and molecular epidemiology of the largest cohort of HSP in Greece, comprising 54 patients from 40 families. We used a targeted next-generation sequencing (NGS) approach to genetically assess a proband from each family. We made a genetic diagnosis in >50% of cases and identified 11 novel variants. Variants in SPAST and KIF5A were the most common causes of autosomal dominant HSP, whereas SPG11 and CYP7B1 were the most common cause of autosomal recessive HSP. We identified a novel variant in SPG11, which led to disease with later onset and may be unique to the Greek population and report the first nonsense mutation in KIF5A. Interestingly, the frequency of HSP mutations in the Greek population, which is relatively isolated, was very similar to other European populations. We confirm that NGS approaches are an efficient diagnostic tool and should be employed early in the assessment of HSP patients.
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PMID:Hereditary spastic paraplegia in Greece: characterisation of a previously unexplored population using next-generation sequencing. 2637 31


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