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

Spinocerebellar ataxial 1 (SCA1) is the locus name of autosomal dominant olivopontocerebellar atrophy (OPCA), and is assigned to the short arm of chromosome 6. The tight linkage between SCA1 and D6S89 has recently been reported. In order to examine possible locus heterogeneity, we studied linkage for D6S89 to disease loci in 16 pedigrees of dominant OPCA. D6S89 polymorphism was analysed with PCR amplification of genomic DNA by using specific oligonucleotide primers. Lod scores were computed by LIPED program with the correction of age-dependent penetrance. Homogeneity test was performed by using HOMOG program. Fifteen out of 16 pedigrees were informative to D6S89. Among them, 7 pedigrees showed positive and 8 pedigrees showed negative lod scores throughout all recombination fractions. Homogeneity testing disclosed that approximately 55% of pedigrees are linked to D6S89, and others were not linked. Our results provide evidences that dominant OPCA in Japan are genetically heterogenous. At now, it has been still unknown whether there are any clinico-pathological differences among OPCA genotypes. Based on the alpha-constant from homogeneity testing, we divided our pedigrees into linked-pedigree (SCA1) and nonlinked-pedigrees (nonSCA1). Then, clinical features were compared between these two groups. Hyperactive DTR was more common in SCA1 than nonSCA1 group. On the other hand, hypoactive DTR was more significantly dominated in nonSCA1 than SCA1. Slow saccade and Babinski sign were common in both groups. Although not statistically significant, nystagmus, exteral ophthalmoparesis, mydriasis, ptosis, facio-lingual twitching, and limb spasticity were more frequently observed in SCA1 than nonSCA1. These results indicate that there are possible correlation between disease genotype and phenotype.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:[Linkage study of hereditary olivopontocerebellar atrophy: genetic evidence for locus heterogeneity in Japanese cases]. 162 32

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

The autosomal dominant hereditary spastic paraplegias (AD-HSP) are a heterogeneous group of degenerative disorders of the central motor system, characterized by progressive spasticity of the lower limbs. Five loci for pure AD-HSP have been identified to date: SPG3 at 14q, SPG4 at 2p, SPG6 at 15q, SPG8 at 8q, and more recently SPG10 at 12q. We have analyzed a Brazilian family with 16 affected individuals by pure AD-HSP who developed progressive gait disturbance with onset at age 18-26 years. Linkage analysis performed with 13 relatives (6 affected and 7 normal) excluded SPG3, SPG4, and SPG6 as candidate regions. However, positive LOD scores were obtained with markers flanking the candidate region for the SPG8 locus [maximum two point Lod score (Zmax) = 3.3 at theta = 0 for D8S1804]. In this region lies the syntrophin beta 1 gene (SNT2B1), a widely expressed dystrophin-associated protein and therefore a good positional and functional candidate for this disease. Immunohistochemical and Western Blot (WB) studies showed that the distribution, expression, and apparent molecular weight of the beta 1 syntrophin protein were comparable to those of normal control individuals. Therefore, it is unlikely that defects in this protein are related to SPG8, at least in the present family.
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PMID:Brazilian family with pure autosomal dominant spastic paraplegia maps to 8q: analysis of muscle beta 1 syntrophin. 1079 36