Features Of Hereditary Spastic Paraplegia Research Articles

Clinical and genetic characterization of hereditary spastic paraplegia type 3A in Taiwan

AimTo investigate the clinical and genetic features of hereditary spastic paraplegia (HSP) type 3A (SPG3A) in Taiwan. MethodsMutational analysis of the ATL1 gene was performed for 274 unrelated Taiwanese HSP patients. The diagnosis of SPG3A was ascertained by the presence of a heterozygous pathogenic mutation in ATL1. The SPG3A patients received clinical, electrophysiological, and neuroimaging evaluations. Disease severity was assessed by using Spastic Paraplegia Rating Scale (SPRS) and disability score. Nineteen single nucleotide polymorphism (SNP) markers flanking ATL1 were genotyped for haplotype analysis of ATL1 p.R416C mutation. ResultsEighteen SPG3A patients from 11 families were identified. They typically presented a pure form HSP phenotype with disease onset ranging from age 1–68 years. Five heterozygous ATL1 mutations were identified, including p.R239C, p.V253I, p.Y336H, p.P342R and p.R416C. ATL1 p.R416C was the most common mutation and presented in five SPG3A pedigrees. Haplotype analyses demonstrated a shared haplotype in the 12 individuals carrying a p.R416C allele. ConclusionSPG3A accounts for 4% (11 out of 274) of HSP in the Taiwanese cohort. Patents with the ATL1 p.R416C mutation in Taiwan may descend from a common ancestor. This study defines the clinical and genetic features of SPG3A in Taiwan and provides useful information for the diagnosis and management, especially in patients of Han Chinese descent.

Loss of Enzyme Activity in Mutated B4GALNT1 Gene Products in Patients with Hereditary Spastic Paraplegia Results in Relatively Mild Neurological Disorders: Similarity with Phenotypes of B4galnt1 Knockout Mice

B4GALNT1 is an enzyme essential for the synthesis of complex gangliosides, whose absence leads to progressive neurodegeneration with aging in mice. Recently, eleven cases of hereditary spastic paraplegia with mutation in the coding region of B4GALNT1 were reported. However, changes in the enzymatic activity of their products have never been studied. We have constructed expression vectors for individual mutant cDNAs, and examined their activities by cell-free in vitro enzyme assays, and flow cytometry of cells transfected with their expression vectors. Among them, almost all mutant genes showed the complete loss of B4GALNT1 activity in both the in vitro enzyme assays and flow cytometry. Two mutants exceptionally showed weak activity. One of them, M4, had a mutation at amino acid 228 with a premature termination codon. Interestingly, the intensity of fluorescence of GM2 measured by flow cytometry was equivalent between the WT and M4 mutant, although the positive cell population was relatively small in M4. Western immunoblotting of cell lysates from transfectants with cDNA plasmids revealed 67-kDa bands except those containing premature termination codons or frame-shift mutation. Taken together with the clinical findings of patients, loss of enzyme activity may be responsible for the clinical features of hereditary spastic paraplegia, whereas the intensity of neurological disorders was relatively milder than expected. These clinical features of patients including those with male hypogonadism are very similar to the abnormal phenotypes detected in B4galnt1-deficient mice.

Hereditary and idiopathic spastic paraparesis: preliminary findings of a single center experience

ABSTRACTObjectives: Hereditary spastic paraplegias (HSP) is a heterogeneous group of inherited neurologic disorders with diversified clinical manifestations. The purpose of this study was to summarize the clinical manifestations of HSP by analyzing the clinical data of 56 HSP patients.Methods: A total of 56 HSP patients treated in our hospital from January 2014 to March 2016 were included. Demographic and clinical characteristics of patients were collected. The severity of HSP was assessed by disease severity score.Results: The patients included 40 males and 16 females. The mean onset age was 17.86 ± 12.56 years (range: 1–47). The mean disease duration was 13.46 ± 12.82 years (range: 1–63). There were 29 pure (51.8%) forms and 27 complicated (48.2%) HSP. The common manifestations included increased deep tendon reflexes in the lower extremities (94.6%), positive Babinski sign (94.6%), increased muscle tone of lower extremities (91.1%), scissors gait (83.9%), ankle clonus (69.6%), reduced muscle strength in the lower extremities (48.2%) and skeletal deformities (37.5%). Reduced cognitive function was the most common manifestation (55.6%) of the complicated HSP patients. The mean disease severity score was significantly higher in males than in females (2.75 ± 0.55 vs. 2.18 ± 1.13, P = 0.013). Patients with a disease duration >30 years had a significantly higher disease severity score than those with disease duration of 1–10 and 21–30 years.Discussion: We reported the clinical features of HSP from 56 patients in our hospital. Our findings should be helpful for better understanding of clinical features of HSP.

Features of hereditary spastic paraplegias in North African region

Features of hereditary spastic paraplegias in North African region

Pathophysiology, diagnostic work-up and management of balance impairments and falls in patients with hereditary spastic paraplegia.

Balance impairments are common in patients with hereditary spastic paraplegia and are among the most debilitating symptoms, as they frequently result in falls and fall-related injuries. Several features of hereditary spastic paraplegia contribute to balance impairments and multiple treatment options exist. However, an overview of these underlying mechanisms and their treatment is currently lacking. This paper reviews the pathophysiology, diagnostic workup, and management of balance impairments in hereditary spastic paraplegia. Recommendations are based on scientific evidence, when available, and otherwise reflect practice-based evidence supported by clinical experience. Through diligent history-taking and clinical examination, followed by multidisciplinary treatment tailored to the identified underlying mechanisms, balance capacities can be improved in patients with hereditary spastic paraplegia and at least a proportion of falls can be prevented.

Clinical and genetic study of hereditary spastic paraplegia in Canada.

Objective:To describe the clinical, genetic, and epidemiologic features of hereditary spastic paraplegia (HSP) in Canada and to determine which clinical, radiologic, and genetic factors determine functional outcomes for patients with HSP.Methods:We conducted a multicenter observational study of patients who met clinical criteria for the diagnosis of HSP in the provinces of Alberta, Ontario, and Quebec from 2012 to 2015. Characteristics of the participants were analyzed using descriptive statistics. The main outcome measure for a subset of the cohort (n = 48) was the Spastic Paraplegia Rating Scale. We also used the SPATAX-EUROSPA disability stage (disability score) to assess disability (n = 65).Results:A total of 526 patients were identified with HSP across the country, and 150 patients had a confirmed genetic diagnosis. Mutations were identified in 15 different genes; the most common were SPAST (SPG4, 48%), ATL1 (SPG3A, 16%), SPG11 (8%), SPG7 (7%), and KIAA0196 (SPG8, 5%). The diagnosis of SPG4 was associated with older age at symptom onset (p = 0.0017). SPG4 and SPG3A were less associated with learning disabilities compared to other subtypes of HSP, and SPG11 was strongly associated with progressive cognitive deficits (odds ratio 87.75, 95% confidence interval 14.04–548.24, p < 0.0001). SPG3A was associated with better functional outcomes compared to other HSP subtypes (p = 0.04) on multivariate analysis. The strongest predictor of significant disability was abnormal brain MRI (p = 0.014).Conclusions:The most important predictors of disability in our HSP cohort were SPG11 mutations and abnormal brain MRI. Accurate molecular characterization of well-phenotyped cohorts and international collaboration are essential to establish the natural history of these rare neurodegenerative disorders.

Clinical features of hereditary spastic paraplegia due to spastin mutation

In the article “Clinical features of hereditary spastic paraplegia due to spastin mutation” …

Clinical features of hereditary spastic paraplegia due to spastin mutation

Mutations in the spastin gene are the commonest cause of hereditary spastic paraparesis (HSP), accounting for up to 40% of autosomal dominant cases. The phenotype associated with HSP due to mutation in the spastin gene (SPG4) tends to be pure HSP. To characterize in more detail the genetic and phenotypic characteristics of SPG4 by examining a large cohort of patients with HSP. The authors identified patients who tested positive for spastin mutation using a direct sequencing approach of all exons. The authors identified spastin mutations in 53 patients. Twenty-seven of the mutations identified were novel. The phenotype in the majority of patients was of pure HSP. In one individual, a complicated phenotype with progressive bulbar dysfunction and respiratory insufficiency was observed. Evidence of lower motor neuron dysfunction in a subgroup of SPG4 patients was identified. The missense changes S44L and P45Q were identified in patients with other spastin mutations and seemed to be exerting a phenotype-modifying effect. These findings add to the number of spastin mutations identified and demonstrate the importance of screening the whole gene, given the possibility of double mutations and intragenic modifiers. The identification of the complicated phenotypes has important implications for identifying the phenotype of patients in whom spastin screening should be considered. The presence of lower motor neuron dysfunction in a subgroup of SPG4 patients suggests that the cellular dysfunction in SPG4 extends beyond the axonal projections of upper motor neurons and ascending sensory pathways.