| 1. |
- van Rheenen, Wouter, et al.
(författare)
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Genome-wide association analyses identify new risk variants and the genetic architecture of amyotrophic lateral sclerosis
- 2016
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Ingår i: Nature Genetics. - : Springer Science and Business Media LLC. - 1061-4036 .- 1546-1718. ; 48:9, s. 1043-1048
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Tidskriftsartikel (refereegranskat)abstract
- To elucidate the genetic architecture of amyotrophic lateral sclerosis (ALS) and find associated loci, we assembled a custom imputation reference panel from whole-genome-sequenced patients with ALS and matched controls (n = 1,861). Through imputation and mixed-model association analysis in 12,577 cases and 23,475 controls, combined with 2,579 cases and 2,767 controls in an independent replication cohort, we fine-mapped a new risk locus on chromosome 21 and identified C21orf2 as a gene associated with ALS risk. In addition, we identified MOBP and SCFD1 as new associated risk loci. We established evidence of ALS being a complex genetic trait with a polygenic architecture. Furthermore, we estimated the SNP-based heritability at 8.5%, with a distinct and important role for low-frequency variants (frequency 1-10%). This study motivates the interrogation of larger samples with full genome coverage to identify rare causal variants that underpin ALS risk.
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| 2. |
- Nicolas, Aude, et al.
(författare)
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Genome-wide Analyses Identify KIF5A as a Novel ALS Gene
- 2018
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Ingår i: Neuron. - : Cell Press. - 0896-6273 .- 1097-4199. ; 97:6, s. 1268-1283.e6
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Tidskriftsartikel (refereegranskat)abstract
- To identify novel genes associated with ALS, we undertook two lines of investigation. We carried out a genome-wide association study comparing 20,806 ALS cases and 59,804 controls. Independently, we performed a rare variant burden analysis comparing 1,138 index familial ALS cases and 19,494 controls. Through both approaches, we identified kinesin family member 5A (KIF5A) as a novel gene associated with ALS. Interestingly, mutations predominantly in the N-terminal motor domain of KIF5A are causative for two neurodegenerative diseases: hereditary spastic paraplegia (SPG10) and Charcot-Marie-Tooth type 2 (CMT2). In contrast, ALS-associated mutations are primarily located at the C-terminal cargo-binding tail domain and patients harboring loss-of-function mutations displayed an extended survival relative to typical ALS cases. Taken together, these results broaden the phenotype spectrum resulting from mutations in KIF5A and strengthen the role of cytoskeletal defects in the pathogenesis of ALS.
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| 3. |
- Al-Chalabi, Ammar, et al.
(författare)
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July 2017 ENCALS statement on edaravone
- 2017
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Ingår i: Amyotrophic Lateral Sclerosis and Frontotemporal Degeneration. - : TAYLOR & FRANCIS LTD. - 2167-8421 .- 2167-9223. ; 18:7-8, s. 471-474
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Tidskriftsartikel (refereegranskat)abstract
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| 4. |
- Alix, James J. P., et al.
(författare)
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Assessment of the reliability of the motor unit size index (MUSIX) in single subject "round-robin" and multi-centre settings
- 2019
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Ingår i: Clinical Neurophysiology. - : ELSEVIER IRELAND LTD. - 1388-2457 .- 1872-8952. ; 130:5, s. 666-674
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Tidskriftsartikel (refereegranskat)abstract
- Objective: The motor unit size index (MUSIX) is incorporated into the motor unit number index (MUNIX). Our objective was to assess the intra-/inter-rater reliability of MUSIX in healthy volunteers across single subject "round robin" and multi-centre settings.Methods: Data were obtained from (i) a round-robin assessment in which 12 raters (6 with prior experience and 6 without) assessed six muscles (abductor pollicis brevis, abductor digiti minimi, biceps brachii, tibialis anterior, extensor digitorum brevis and abductor hallucis) and (ii) a multi-centre study with 6 centres studying the same muscles in 66 healthy volunteers. Intrafinter-rater data were provided by 5 centres, 1 centre provided only intra-rater data. Intrafinter-rater variability was assessed using the coefficient of variation (COV), Bland-Altman plots, bias and 95% limits of agreement.Results: In the round-robin assessment intra-rater COVs for MUSIX ranged from 7.8% to 28.4%. Inter-rater variability was between 7.8% and 16.2%. Prior experience did not impact on MUSIX values. In the multi-centre study MUSIX was more consistent than the MUNIX. Abductor hallucis was the least reliable muscle.Conclusions: The MUSIX is a reliable neurophysiological biomarker of reinnervation.Significance: MUSIX could provide insights into the pathophysiology of a range of neuromuscular disorders, providing a quantitative biomarker of reinnervation.
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| 5. |
- Brenner, David, et al.
(författare)
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Hot-spot KIF5A mutations cause familial ALS
- 2018
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Ingår i: Brain. - : Oxford University Press. - 0006-8950 .- 1460-2156. ; 141, s. 688-697
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Tidskriftsartikel (refereegranskat)abstract
- Heterozygous missense mutations in the N-terminal motor or coiled-coil domains of the kinesin family member 5A (KIF5A) gene cause monogenic spastic paraplegia (HSP10) and Charcot-Marie-Tooth disease type 2 (CMT2). Moreover, heterozygous de novo frame-shift mutations in the C-terminal domain of KIF5A are associated with neonatal intractable myoclonus, a neurodevelopmental syndrome. These findings, together with the observation that many of the disease genes associated with amyotrophic lateral sclerosis disrupt cytoskeletal function and intracellular transport, led us to hypothesize that mutations in KIF5A are also a cause of amyotrophic lateral sclerosis. Using whole exome sequencing followed by rare variant analysis of 426 patients with familial amyotrophic lateral sclerosis and 6137 control subjects, we detected an enrichment of KIF5A splice-site mutations in amyotrophic lateral sclerosis (2/426 compared to 0/6137 in controls; P = 4.2 x 10-3), both located in a hot-spot in the C-terminus of the protein and predicted to affect splicing exon 27. We additionally show co-segregation with amyotrophic lateral sclerosis of two canonical splice-site mutations in two families. Investigation of lymphoblast cell lines from patients with KIF5A splice-site mutations revealed the loss of mutant RNA expression and suggested haploinsufficiency as the most probable underlying molecular mechanism. Furthermore, mRNA sequencing of a rare non-synonymous missense mutation (predicting p. Arg1007Gly) located in the C-terminus of the protein shortly upstream of the splice donor of exon 27 revealed defective KIF5A pre-mRNA splicing in respective patient-derived cell lines owing to abrogation of the donor site. Finally, the non-synonymous single nucleotide variant rs113247976 (minor allele frequency = 1.00% in controls, n = 6137), also located in the C-terminal region [p.(Pro986Leu) in exon 26], was significantly enriched in familial amyotrophic lateral sclerosis patients (minor allele frequency = 3.40%; P = 1.28 x 10-7). Our study demonstrates that mutations located specifically in a C-terminal hotspot of KIF5A can cause a classical amyotrophic lateral sclerosis phenotype, and underline the involvement of intracellular transport processes in amyotrophic lateral sclerosis pathogenesis.
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| 6. |
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| 7. |
- De Carvalho, Mamede, et al.
(författare)
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International Survey of ALS Experts about Critical Questions for Assessing Patients with ALS
- 2017
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Ingår i: Amyotrophic Lateral Sclerosis and Frontotemporal Degeneration. - : Taylor & Francis. - 2167-8421 .- 2167-9223. ; 18:7-8, s. 505-510
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Tidskriftsartikel (refereegranskat)abstract
- Objective: To define an applicable dataset for ALS patient registries we weighted specific clinical items as scored by worldwide ALS experts.Methods: Sixty participants were invited based on relevant clinical work, publications and personal acquaintance. They rated 160 clinical items consensually agreed by the members of our project, incorporating specialists from five European Centres. Scoring scheme was defined as: 1 - essential; 2 - important; 3 - not very important. A mixed effect model was applied to rank items and to find possible correlations with geographical region (Europe vs. outside Europe).Results: We received 40 responses, 20 from Europe and 20 from outside; 42/160 data were scored as essential by >50% of the respondents, including: date of birth, gender, date of disease onset, date of diagnosis, ethnicity, region of onset, predominant upper neuron (UMN) or lower motor neuron (LMN) impairment, proximal versus distal weakness, respiratory symptoms, dysarthria, weight loss, signs of LMN/UMN involvement, emotional incontinence, cognitive changes, respiratory signs, neck weakness, body mass index, ALSFRS-R at entry, ALSFRS-R subscores at entry, timing and pattern of spreading and staging, electromyography, spirometry, MRI, CK level, riluzole intake, genetic background, history of physical exercise and previous and current main occupation. Four components were scored as non-relevant, including place of birth, blood pressure and pain at onset. There was no significant difference between regions (European vs. non-European countries).Conclusions: Our study identified a consensual set of clinical data with 42 specific items that can be used as a minimal data set for patient registers and for clinical trials.
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| 8. |
- de Carvalho, Mamede, et al.
(författare)
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Peripheral neuropathy in ALS : Phenotype association
- 2018
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Ingår i: Journal of the peripheral nervous system. - : John Wiley & Sons. - 1085-9489 .- 1529-8027. ; 23:4, s. 391-392
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Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)
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| 9. |
- Freischmidt, Axel, et al.
(författare)
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Haploinsufficiency of TBK1 causes familial ALS and fronto-temporal dementia
- 2015
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Ingår i: Nature Neuroscience. - : Springer Science and Business Media LLC. - 1097-6256 .- 1546-1726. ; 18:5, s. 631-
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Tidskriftsartikel (refereegranskat)abstract
- Amyotrophic lateral sclerosis (ALS) is a genetically heterogeneous neurodegenerative syndrome hallmarked by adult-onset loss of motor neurons. We performed exome sequencing of 252 familial ALS (fALS) and 827 control individuals. Gene-based rare variant analysis identified an exome-wide significant enrichment of eight loss-of-function (LoF) mutations in TBK1 (encoding TANK-binding kinase 1) in 13 fALS pedigrees. No enrichment of LoF mutations was observed in a targeted mutation screen of 1,010 sporadic ALS and 650 additional control individuals. Linkage analysis in four families gave an aggregate LOD score of 4.6. In vitro experiments confirmed the loss of expression of TBK1 LoF mutant alleles, or loss of interaction of the C-terminal TBK1 coiled-coil domain (CCD2) mutants with the TBK1 adaptor protein optineurin, which has been shown to be involved in ALS pathogenesis. We conclude that haploinsufficiency of TBK1 causes ALS and fronto-temporal dementia.
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| 10. |
- Gromicho, Marta, et al.
(författare)
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Frequency of C9orf72 hexanucleotide repeat expansion and SOD1 mutations in Portuguese patients with amyotrophic lateral sclerosis
- 2018
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Ingår i: Neurobiology of Aging. - : Elsevier. - 0197-4580 .- 1558-1497. ; 70
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Tidskriftsartikel (refereegranskat)abstract
- Mutation frequency of the 2 main amyotrophic lateral sclerosis (ALS) erelated genes, C9orf72 and SOD1, varies considerably across the world. We analyzed those genes in a large population of Portuguese ALS patients (n = 371) and recorded demographic and clinical features. Familial ALS (FALS) was disclosed in 11.6% of patients. Mutations in either SOD1 or C9orf72 were found in 9.2% of patients and accounted for 40% of FALS and 5.2% of sporadic ALS. SOD1 mutations were rare (0.83%), but a novel and probably disease-causing mutation was identified: p. Ala152Pro (c. 457G>C). The C9orf72 hexanucleotide repeat expansion was the commonest abnormality, accounting for 4.6% of sporadic ALS and 37.5% of FALS; in these patients, Frontotemporal Dementia was prevalent. This first report on the frequency of C9orf72 hexanucleotide repeat expansion and SOD1 mutations in Portuguese ALS patients reiterate that the genetic architecture of ALS varies among different geographic regions. The mutations incidence in ALS patients (w10%) and associated phenotypes suggest that genetic tests should be offered to more patients, and other genes should be investigated in our population.
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