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Amyotrophic lateral sclerosis (ALS) is caused by upper and lower motor neuron loss and has a fairly rapid disease progression, leading to fatality in an average of 2-5 years after symptom onset. Numerous genes have been implicated in this disease; however, many cases remain unexplained. Several technologies are being used to identify regions of interest and investigate candidate genes. Initial approaches to detect ALS genes include, among others, linkage analysis, Sanger sequencing, and genome-wide association studies. More recently, next-generation sequencing methods, such as whole-exome and whole-genome sequencing, have been introduced. While those methods have been particularly useful in discovering new ALS-linked genes, methodological advances are becoming increasingly important, especially given the complex genetics of ALS. Novel sequencing technologies, like long-read sequencing, are beginning to be used to uncover the contribution of repeat expansions and other types of structural variation, which may help explain missing heritability in ALS. In this review, we discuss how popular and/or upcoming methods are being used to discover ALS genes, highlighting emerging long-read sequencing platforms and their role in aiding our understanding of this challenging disease.

Arginine-rich dipeptide repeat proteins (R-DPRs), abnormal translational products of a GGGGCC hexanucleotide repeat expansion in

Arginine-rich dipeptide repeat proteins (R-DPRs), abnormal translational products of a GGGGCC hexanucleotide repeat expansion in C9ORF72 , play a critical role in C9ORF72 -related amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD), the most common genetic form of the disorders (c9ALS/FTD). R-DPRs form liquid condensates in vitro, induce stress granule formation in cultured cells, aggregate, and sometimes coaggregate with TDP-43 in postmortem tissue from patients with c9ALS/FTD. However, how these processes are regulated is unclear. Here, we show that loss of poly(ADP-ribose) (PAR) suppresses neurodegeneration in c9ALS/FTD fly models and neurons differentiated from patient-derived induced pluripotent stem cells. Mechanistically, PAR induces R-DPR condensation and promotes R-DPR–induced stress granule formation and TDP-43 aggregation. Moreover, PAR associates with insoluble R-DPR and TDP-43 in postmortem tissue from patients. These findings identified PAR as a promoter of R-DPR toxicity and thus a potential target for treating c9ALS/FTD.

To examine the length of a hexanucleotide expansion in C9orf72, which represents the most frequent genetic cause of frontotemporal lobar degeneration and motor neuron disease, we employed a targeted amplification-free long-read sequencing technology: No-Amp sequencing. In our cross-sectional study, we assessed cerebellar tissue from 28 well-characterized C9orf72 expansion carriers. We obtained 3507 on-target circular consensus sequencing reads, of which 814 bridged the C9orf72 repeat expansion (23%). Importantly, we observed a significant correlation between expansion sizes obtained using No-Amp sequencing and Southern blotting (P = 5.0 × 10−4). Interestingly, we also detected a significant survival advantage for individuals with smaller expansions (P = 0.004). Additionally, we uncovered that smaller expansions were significantly associated with higher levels of C9orf72 transcripts containing intron 1b (P = 0.003), poly(GP) proteins (P = 1.3 × 10− 5), and poly(GA) proteins (P = 0.005). Thorough examination of the composition of the expansion revealed that its GC content was extremely high (median: 100%) and that it was mainly composed of GGGGCC repeats (median: 96%), suggesting that expanded C9orf72 repeats are quite pure. Taken together, our findings demonstrate that No-Amp sequencing is a powerful tool that enables the discovery of relevant clinicopathological associations, highlighting the important role played by the cerebellar size of the expanded repeat in C9orf72-linked diseases., DeJesus-Hernandez et al. employ an innovative long-read sequencing method to examine the length of the expanded C9orf72 repeat that represents the most common genetic cause of frontotemporal dementia and amyotrophic lateral sclerosis. Smaller expansion size confers a survival benefit for patients.

Since the discovery of the C9orf72 repeat expansion as the most common genetic cause of frontotemporal dementia (FTD) and amyotrophic lateral sclerosis, it has increasingly been associated with a wider spectrum of phenotypes, including other types of dementia, movement disorders, psychiatric symptoms and slowly progressive FTD. Prompt recognition of patients with C9orf72-associated diseases is essential in light of upcoming clinical trials. The striking clinical heterogeneity associated with C9orf72 repeat expansions remains largely unexplained. In contrast to other repeat expansion disorders, evidence for an effect of repeat length on phenotype is inconclusive. Patients with C9orf72-associated diseases typically have very long repeat expansions, containing hundreds to thousands of GGGGCC-repeats, but smaller expansions might also have clinical significance. The exact threshold at which repeat expansions lead to neurodegeneration is unknown, and discordant cut-offs between laboratories pose a challenge for genetic counselling. Accurate and large-scale measurement of repeat expansions has been severely hindered by technical difficulties in sizing long expansions and by variable repeat lengths across and within tissues. Novel long-read sequencing approaches have produced promising results and open up avenues to further investigate this enthralling repeat expansion, elucidating whether its length, purity, and methylation pattern might modulate clinical features of C9orf72-related diseases.

No treatment for frontotemporal dementia (FTD), the second most common type of early-onset dementia, is available, but therapeutics are being investigated to target the 2 main proteins associated with FTD pathological subtypes: TDP-43 (FTLD-TDP) and tau (FTLD-tau). Testing potential therapies in clinical trials is hampered by our inability to distinguish between patients with FTLD-TDP and FTLD-tau. Therefore, we evaluated truncated stathmin-2 (STMN2) as a proxy of TDP-43 pathology, given the reports that TDP-43 dysfunction causes truncated STMN2 accumulation. Truncated STMN2 accumulated in human induced pluripotent stem cell-derived neurons depleted of TDP-43, but not in those with pathogenic TARDBP mutations in the absence of TDP-43 aggregation or loss of nuclear protein. In RNA-Seq analyses of human brain samples from the NYGC ALS cohort, truncated STMN2 RNA was confined to tissues and disease subtypes marked by TDP-43 inclusions. Last, we validated that truncated STMN2 RNA was elevated in the frontal cortex of a cohort of patients with FTLD-TDP but not in controls or patients with progressive supranuclear palsy, a type of FTLD-tau. Further, in patients with FTLD-TDP, we observed significant associations of truncated STMN2 RNA with phosphorylated TDP-43 levels and an earlier age of disease onset. Overall, our data uncovered truncated STMN2 as a marker for TDP-43 dysfunction in FTD.

Amyotrophic lateral sclerosis (ALS) and frontotemporal lobar degeneration (FTLD) are two devastating and fatal neurodegenerative conditions. While distinct, they share many clinical, genetic, and pathological characteristics1, and both show selective vulnerability of layer 5b extratelencephalic-projecting cortical populations, including Betz cells in ALS2,3 and von Economo neurons (VENs) in FTLD4,5. Here, we report the first high resolution single-cell atlas of the human primary motor cortex (MCX) and its transcriptional alterations in ALS and FTLD across ~380,000 nuclei from 64 individuals, including 17 control samples and 47 sporadic and C9orf72-associated ALS and FTLD patient samples. We identify 46 transcriptionally distinct cellular subtypes including two Betz-cell subtypes, and we observe a previously unappreciated molecular similarity between Betz cells and VENs of the prefrontal cortex (PFC) and frontal insula. Many of the dysregulated genes and pathways are shared across excitatory neurons, including stress response, ribosome function, oxidative phosphorylation, synaptic vesicle cycle, endoplasmic reticulum protein processing, and autophagy. Betz cells and SCN4B+ long-range projecting L3/L5 cells are the most transcriptionally affected in both ALS and FTLD. Lastly, we find that the VEN/Betz cell-enriched transcription factor, POU3F1, has altered subcellular localization, co-localizes with TDP-43 aggregates, and may represent a cell type-specific vulnerability factor in the Betz cells of ALS and FTLD patient tissues.

Spinocerebellar ataxia type 3 (SCA3), caused by a CAG repeat expansion in the ataxin-3 gene (ATXN3), is characterized by neuronal polyglutamine (polyQ) ATXN3 protein aggregates. Although there is no cure for SCA3, gene-silencing approaches to reduce toxic polyQ ATXN3 showed promise in preclinical models. However, a major limitation in translating putative treatments for this rare disease to the clinic is the lack of pharmacodynamic markers for use in clinical trials. Here, we developed an immunoassay that readily detects polyQ ATXN3 proteins in human biological fluids and discriminates patients with SCA3 from healthy controls and individuals with other ataxias. We show that polyQ ATXN3 serves as a marker of target engagement in human fibroblasts, which may bode well for its use in clinical trials. Last, we identified a single-nucleotide polymorphism that strongly associates with the expanded allele, thus providing an exciting drug target to abrogate detrimental events initiated by mutant ATXN3. Gene-silencing strategies for several repeat diseases are well under way, and our results are expected to improve clinical trial preparedness for SCA3 therapies.

Author(s): Ramos, Eliana Marisa; Dokuru, Deepika Reddy; Van Berlo, Victoria; Wojta, Kevin; Wang, Qing; Huang, Alden Y; Deverasetty, Sandeep; Qin, Yue; van Blitterswijk, Marka; Jackson, Jazmyne; Appleby, Brian; Bordelon, Yvette; Brannelly, Patrick; Brushaber, Danielle E; Dickerson, Bradford; Dickinson, Susan; Domoto-Reilly, Kimiko; Faber, Kelley; Fields, Julie; Fong, Jamie; Foroud, Tatiana; Forsberg, Leah K; Gavrilova, Ralitza; Ghoshal, Nupur; Goldman, Jill; Graff-Radford, Jonathan; Graff-Radford, Neill; Grant, Ian; Grossman, Murray; Heuer, Hilary W; Hsiung, Ging-Yuek R; Huey, Edward; Irwin, David; Kantarci, Kejal; Karydas, Anna; Kaufer, Daniel; Kerwin, Diana; Knopman, David; Kornak, John; Kramer, Joel H; Kremers, Walter; Kukull, Walter; Litvan, Irene; Ljubenkov, Peter; Lungu, Codrin; Mackenzie, Ian; Mendez, Mario F; Miller, Bruce L; Onyike, Chiadi; Pantelyat, Alexander; Pearlman, Rodney; Petrucelli, Len; Potter, Madeline; Rankin, Katherine P; Rascovsky, Katya; Roberson, Erik D; Rogalski, Emily; Shaw, Leslie; Syrjanen, Jeremy; Tartaglia, Maria Carmela; Tatton, Nadine; Taylor, Joanne; Toga, Arthur; Trojanowski, John Q; Weintraub, Sandra; Wong, Bonnie; Wszolek, Zbigniew; Rademakers, Rosa; Boeve, Brad F; Rosen, Howard J; Boxer, Adam L; ARTFL/LEFFTDS consortium; Coppola, Giovanni | Abstract: IntroductionThe Advancing Research and Treatment for Frontotemporal Lobar Degeneration (ARTFL) and Longitudinal Evaluation of Familial Frontotemporal Dementia Subjects (LEFFTDS) consortia are two closely connected studies, involving multiple North American centers that evaluate both sporadic and familial frontotemporal dementia (FTD) participants and study longitudinal changes.MethodsWe screened the major dementia-associated genes in 302 sporadic and 390 familial (symptomatic or at-risk) participants enrolled in these studies.ResultsAmong the sporadic patients, 16 (5.3%) carried chromosome 9 open reading frame 72 (C9orf72), microtubule-associated protein tau (MAPT), and progranulin (GRN) pathogenic variants, whereas in the familial series we identified 207 carriers from 146 families. Of interest, one patient was found to carry a homozygous C9orf72 expansion, while another carried both a C9orf72 expansion and a GRN pathogenic variant. We also identified likely pathogenic variants in the TAR DNA binding protein (TARDBP), presenilin 1 (PSEN1), and valosin containing protein (VCP) genes, and a subset of variants of unknown significance in other rare FTD genes.DiscussionOur study reports the genetic characterization of a large FTD series and supports an unbiased sequencing screen, irrespective of clinical presentation or family history.

Additional file 1 Table S1. Characteristics of overall cohort; Table S2. Characteristics of expression cohort; Figure S1. Comparison blood and brain; Figure S2. Southern blot examples.

Background and ObjectivesTo perform the first screen of 44 amyotrophic lateral sclerosis (ALS) genes in a cohort of African genetic ancestry individuals with ALS using whole-genome sequencing (WGS) data.MethodsOne hundred three consecutive cases with probable/definite ALS (using the revised El Escorial criteria), and self-categorized as African genetic ancestry, underwent WGS using various Illumina platforms. As population controls, 238 samples from various African WGS data sets were included. Our analysis was restricted to 44 ALS genes, which were curated for rare sequence variants and classified according to the American College of Medical Genetics guidelines as likely benign, uncertain significance, likely pathogenic, or pathogenic variants.ResultsThirteen percent of 103 ALS cases harbored pathogenic variants; 5 different SOD1 variants (N87S, G94D, I114T, L145S, and L145F) in 5 individuals (5%, 1 familial case), pathogenic C9orf72 repeat expansions in 7 individuals (7%, 1 familial case) and a likely pathogenic ANXA11 (G38R) variant in 1 individual. Thirty individuals (29%) harbored ≥1 variant of uncertain significance; 10 of these variants had limited pathogenic evidence, although this was insufficient to permit confident classification as pathogenic.DiscussionOur findings show that known ALS genes can be expected to identify a genetic cause of disease in >11% of sporadic ALS cases of African genetic ancestry. Similar to European cohorts, the 2 most frequent genes harboring pathogenic variants in this population group are C9orf72 and SOD1.

Primary lateral sclerosis (PLS) is a condition that most neurologists will never personally diagnose. For the estimated several thousand people living with PLS globally, while it may not be life-sh...

Frontotemporal lobar degeneration with neuronal inclusions of the TAR DNA-binding protein 43 (FTLD-TDP) represents the most common pathological subtype of FTLD. We established the international FTLD-TDP whole-genome sequencing consortium to thoroughly characterize the known genetic causes of FTLD-TDP and identify novel genetic risk factors. Through the study of 1131 unrelated Caucasian patients, we estimated that C9orf72 repeat expansions and GRN loss-of-function mutations account for 25.5% and 13.9% of FTLD-TDP patients, respectively. Mutations in TBK1 (1.5%) and other known FTLD genes (1.4%) were rare, and the disease in 57.7% of FTLD-TDP patients was unexplained by the known FTLD genes. To unravel the contribution of common genetic factors to the FTLD-TDP etiology in these patients, we conducted a two-stage association study comprising the analysis of whole-genome sequencing data from 517 FTLD-TDP patients and 838 controls, followed by targeted genotyping of the most associated genomic loci in 119 additional FTLD-TDP patients and 1653 controls. We identified three genome-wide significant FTLD-TDP risk loci: one new locus at chromosome 7q36 within the DPP6 gene led by rs118113626 (p value = 4.82e - 08, OR = 2.12), and two known loci: UNC13A, led by rs1297319 (p value = 1.27e - 08, OR = 1.50) and HLA-DQA2 led by rs17219281 (p value = 3.22e - 08, OR = 1.98). While HLA represents a locus previously implicated in clinical FTLD and related neurodegenerative disorders, the association signal in our study is independent from previously reported associations. Through inspection of our whole-genome sequence data for genes with an excess of rare loss-of-function variants in FTLD-TDP patients (n >= 3) as compared to controls (n = 0), we further discovered a possible role for genes functioning within the TBK1-related immune pathway (e.g., DHX58, TRIM21, IRF7) in the genetic etiology of FTLD-TDP. Together, our study based on the largest cohort of unrelated FTLD-TDP patients assembled to date provides a comprehensive view of the genetic landscape of FTLD-TDP, nominates novel FTLD-TDP risk loci, and strongly implicates the immune pathway in FTLD-TDP pathogenesis.

Figure S1 a Module-trait relationships are presented for patients with an expanded C9orf72 repeat and patients without this repeat (C9Plus vs. C9Minus). b For patients with an expansion and control subjects (C9Plus vs. Control), module-trait relationships are plotted. These plots are generated with weighted gene co-expression network analysis (WGCNA) to find groups of genes that go up (red) or down (blue) together. A unique color has been assigned to each of these groups, also called a module. Correlations and p-values are shown for variables of interest, including disease group (C9Plus, C9Minus, and/or Control; arrow), neurons, microglia, astrocytes, oligodendrocytes, endothelial cells, RNA integrity number (RIN), age at death, sex, and plate. The strongest correlations (brightest colors) are observed for cell types. Notably, both module-trait relationship plots are based on residuals obtained without adjustment for cell-type-specific markers. Figure S2 a With adjustment for cell-type-specific markers, a cluster dendrogram is shown for C9orf72 expansion carriers and control subjects. b For the same comparison, a cluster dendrogram is displayed without adjustment for cell-type-specific markers. The branches in these dendrograms correspond to specific modules. A unique color has been assigned to each of these modules. Additionally, variables of interest are included, such as the disease group, neurons, microglia, astrocytes, oligodendrocytes, endothelial cells, RNA integrity number (RIN), age at death, sex, and plate. High levels are shown in red and low levels in blue. After adjustment, no striking differences are observed based on cell type; without adjustment, however, modules appear to be associated with certain cell types (e.g., turquoise and neurons). Figure S3 a For patients harboring a C9orf72 repeat expansion and those without this expansion (C9Plus vs. C9Minus; module membership > 0.6 and significance < 1.0E-05), a gene network is displayed. b A gene network is visualized when examining expansion carriers and controls (C9Plus vs. Control; module membership > 0.6 and significance < 1.0E-05). In these network plots, the connectivity of each gene is represented by the size of its node, the module to which it has been assigned by its color, and the strength of the correlation by the thickness of its edges; the C9orf72 gene is denoted by an arrow. Of note, the plots in this figure have been generated without adjustment for cell-type-specific markers. Figure S4 a-d Trends are displayed for patients carrying a C9orf72 repeat expansion. a The first plot shows VEGFA and age at onset. b CDKL1 and C9orf72 expansion size are shown in the second plot. c The third plot displays EEF2K and poly(GP) levels. In these three plots, the solid blue line denotes the linear regression line, while each individual is represented by a solid dark grey circle. d The last plot shows SGSM3 levels and survival after onset, when comparing the bottom 50% (solid salmon line) to the top 50% (solid turquoise line). These plots have been created using residuals unadjusted for differences in cellular composition. Figure S5 a-h The expression levels of VEGFA, CDKL1, EEF2K, and SGSM3 are shown for all disease groups: patients with a C9orf72 repeat expansion (C9Plus), patients without this expansion (C9Minus), and control subjects (Control), both with and without adjustment for cell-type-specific markers. For each box plot, the median is represented by a solid black line, and each box spans the interquartile range (IQR; 25th percentile to 75th percentile). Figure S6 a-h This figure displays the correlation between our expression assays (relative expression) and RNA sequencing data (residuals). a-b The first two plots show correlations for VEGFA, either with or without adjustment for cell-type-specific markers. c-d The next two plots visualize correlations for CDKL1, both with and without adjustment for cellular composition. e-f EEF2K is displayed on the next plots, again with and without adjustment for surrogate markers. g-h The last two plots show correlations for SGSM3 with and without adjustment for cellular composition. For each of these plots, the solid blue line denotes the linear regression line, while each individual is represented by a solid dark grey circle. (PDF 2894 kb)

Noncoding expanded repeats have been implicated in a wide range of diseases. A new report uncovers expanded TTTCA and TTTTA repeats in an intronic region of SAMD12, and at least two other genes, in individuals with benign adult familial myoclonic epilepsy.

Table S1. Tissue samples available and selected for inclusion in this study. Table S2. DEGS in TCX. Positive fold change represents higher gene expression in SS than TT. Negative fold change represents lower gene expression in SS than TT. Table S3. DEGS in CER. Positive fold change represents higher gene expression in SS than TT. Negative fold change represents lower gene expression in SS than TT. Table S4. Overlapping genes between TCX and CER based on top 500 genes with |FC| ≥ 1.2 ranked by unadjusted p value. Table S5. Enrichment of modules for their respective DEG signatures. Table S6. Significant modules identified in the TCX and CER matched cases. Table S7. Significant modules identified in separate disease groups in TCX and CER. Table S8. Significant modules identified in the TCX and CER controls. (DOCX 54 kb)

Objective Suggested C9orf72 disease mechanisms for amyotrophic lateral sclerosis (ALS) and frontotemporal lobar degeneration include C9orf72 haploinsufficiency, G4C2/C4G2 RNA foci, and dipeptide repeat (DPR) proteins translated from the G4C2 expansion; however, the role of small expansions (e.g., 30–90 repeats) is unknown and was investigated here. Methods We conducted a molecular and pathology study of a family in which the father (unaffected at age 90) carried a 70-repeat allele in blood DNA that expanded to ≈1,750 repeats in his children, causing ALS. Results Southern blotting revealed different degrees of mosaicism of small and large expansions in the father's tissues from the CNS. Surprisingly, in each mosaic tissue, C9orf72 mRNA levels were significantly increased compared to an ALS-affected daughter with a large expansion. Increased expression correlated with higher levels of the 70-repeat allele (the upregulation was also evident at the protein level). Remarkably, RNA foci and DPR burdens were similar or even significantly increased (in cerebellum) in the unaffected father compared to the daughter with ALS. However, the father did not display TDP-43 pathology and signs of neurodegeneration. Conclusion The presence of RNA foci and DPR pathology was insufficient for disease manifestation and TDP-43 pathology in the mosaic C9orf72 carrier with upregulated C9orf72 expression. It is important to conduct an investigation of similar cases, which could be found among unaffected parents of sporadic C9orf72 patients (e.g., 21% among Finnish patients with ALS). Caution should be taken when consulting carriers of small expansions because disease manifestation could be dependent on the extent of the somatic instability in disease-relevant tissues.

There is no effective treatment for amyotrophic lateral sclerosis (ALS), a devastating motor neuron disease. However, discovery of a G(4)C(2) repeat expansion in the C9ORF72 gene as the most common genetic cause of ALS has opened up new avenues for therapeutic intervention for this form of ALS. G(4)C(2) repeat expansion RNAs and proteins of repeating dipeptides synthesized from these transcripts are believed to play a key role in C9ORF72-associated ALS (c9ALS). Therapeutics that target G(4)C(2) RNA, such as antisense oligonucleotides (ASOs) and small molecules, are thus being actively investigated. A limitation in moving such treatments from bench to bedside is a lack of pharmacodynamic markers for use in clinical trials. We explored whether poly(GP) proteins translated from G(4)C(2) RNA could serve such a purpose. Poly(GP) proteins were detected in cerebrospinal fluid (CSF) and in peripheral blood mononuclear cells from c9ALS patients and, notably, from asymptomatic C9ORF72 mutation carriers. Moreover, CSF poly(GP) proteins remained relatively constant over time, boding well for their use in gauging biochemical responses to potential treatments. Treating c9ALS patient cells or a mouse model of c9ALS with ASOs that target G(4)C(2) RNA resulted in decreased intracellular and extracellular poly(GP) proteins. This decrease paralleled reductions in G(4)C(2) RNA and downstream G(4)C(2) RNA-mediated events. These findings indicate that tracking poly(GP) proteins in CSF could provide a means to assess target engagement of G(4)C(2) RNA-based therapies in symptomatic C9ORF72 repeat expansion carriers and presymptomatic individuals who are expected to benefit from early therapeutic intervention.

Variants in transmembrane protein 106 B (TMEM106B) modify the disease penetrance of frontotemporal dementia (FTD) in carriers of progranulin (GRN) mutations. We investigated whether TMEM106B is also a genetic modifier of disease in carriers of chromosome 9 open reading frame 72 (C9ORF72) expansions. We assessed the genotype of 325 C9ORF72 expansion carriers (cohort 1), 586 FTD patients lacking C9ORF72 expansions [with or without motor neuron disease (MND); cohort 2], and a total of 1,302 controls for TMEM106B variants (rs3173615 and rs1990622) using MassArray iPLEX and Taqman genotyping assays. For our primary analysis, we focused on functional variant rs3173615, and employed a recessive genotypic model. In cohort 1, patients with C9ORF72 expansions showed a significantly reduced frequency of carriers homozygous for the minor allele as compared to controls [11.9 vs. 19.1 %, odds ratio (OR) 0.57, p = 0.014; same direction as carriers of GRN mutations]. The strongest evidence was provided by FTD patients (OR 0.33, p = 0.009) followed by FTD/MND patients (OR 0.38, p = 0.017), whereas no significant difference was observed in MND patients (OR 0.85, p = 0.55). In cohort 2, the frequency of carriers homozygous for the minor allele was not significantly reduced in patients as compared to controls (OR 0.77, p = 0.079); however, a significant reduction was observed when focusing on those patients with frontotemporal lobar degeneration and TAR DNA-binding protein 43 inclusions (FTLD-TDP; OR 0.26, p < 0.001). Our study identifies TMEM106B as the first genetic factor modifying disease presentation in C9ORF72 expansion carriers. Homozygosity for the minor allele protects carriers from developing FTD, but not from developing MND; similar effects are seen in FTLD-TDP patients with yet unknown genetic causes. These new findings show that the protective effects of TMEM106B are not confined to carriers of GRN mutations and might be relevant for prognostic testing, and as a promising therapeutic target for the entire spectrum of FTLD-TDP.

Background: Amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD) are complex neurodegenerative disorders that can be either sporadic or familial and can overlap clinically and pathologically. We present the first Central-Eastern European family with ALS-FTD syndrome due to a C9ORF72 repeat expansion. Methods: We studied a family consisting of 37 family members, 6 of whom were genetically evaluated for C9ORF72 expansions. Family members were evaluated clinically, by history, and by chart review. Results: Overall, 5 generations of the family were studied, and 6 affected family members were identified. All affected members were females and had a different clinical presentation, which was ALS, FTD or both. Among the genetically evaluated subjects, 5 carried a C9ORF72 expansion; 4 of these individuals remain clinically unaffected. Conclusion: Our report reveals that the hexanucleotide repeat expansion of C9ORF72, which is the most common genetic cause of ALS-FTD complex disorder, is also present in Central-Eastern Europe. Further studies are needed to assess the frequency of this expansion in the Polish population with familial as well as sporadic ALS, FTD and the ALS-FTD complex disorder.

The most common cause of familial frontotemporal lobar degeneration with TAR DNA-binding protein-43 pathology (FTLD-TDP) has been found to be an expansion of a hexanucleotide repeat (GGGGCC) in a noncoding region of the gene C9ORF72. Hippocampal sclerosis (HpScl) is a common finding in FTLD-TDP. Our objective was to screen for the presence of C9ORF72 hexanucleotide repeat expansions in a pathologically confirmed cohort of "pure" hippocampal sclerosis cases (n = 33), outside the setting of FTLD-TDP and Alzheimer's disease (AD). Using a recently described repeat-associated non-ATG (RAN) translation (C9RANT) antibody that was found to be highly specific for c9FTD/ALS, we identified a single "pure" HpScl autopsy case with a repeat expansion in C9ORF72 (c9HpScl). Mutation screening was also performed with repeat-primed polymerase chain reaction and further confirmed with Southern blotting. The c9HpScl patient had a 14-year history of a slowly progressive amnestic syndrome and a clinical diagnosis of probable AD. Neuropsychological testing revealed memory impairment, but no deficits in other cognitive domains. Autopsy showed hippocampal sclerosis with TDP-43 immunoreactive neuronal inclusions relatively limited to limbic lobe structures. Neuritic pathology immunoreactive for p62 was more frequent than TDP-43 in amygdala and hippocampus. Frequent p62-positive neuronal inclusions were present in cerebellar granule neurons as is typical of C9ORF72 mutation carriers. There was no significant FTLD or motor neuron disease. C9RANT was found to be sensitive and specific in this autopsy-confirmed series of HpScl cases. The findings in this patient suggest that the clinical and pathologic spectrum of C9ORF72 repeat expansion is wider than frontotemporal dementia and motor neuron disease, including cases of progressive amnestic dementia with restricted TDP-43 pathology associated with HpScl.

Mutations in profilin-1 (PFN1) have recently been identified in patients with amyotrophic lateral sclerosis (ALS). Because of the considerable overlap between ALS and the common subtype of frontotemporal dementia, which is characterized by transactive response DNA-binding protein 43 pathology (FTLD-TDP), we tested cohorts of ALS and FTLD-TDP patients for PFN1 mutations. DNA was obtained from 342 ALS patients and 141 FTLD-TDP patients at our outpatient clinic and brain bank for neurodegenerative diseases at the Mayo Clinic Florida, Jacksonville, USA. We screened these patients for mutations in coding regions of PFN1 by Sanger sequencing. Subsequently, we used TaqMan genotyping assays to investigate the identified variant in 1167 control subjects. From the results, one variant, p.E117G, was detected in one ALS patient, one FTLD-TDP patient, and two control subjects. The mutation frequency of patients versus control subjects was not significantly different (p-value = 0.36). Moreover, PFN1 and TDP-43 staining of autopsy material did not differ between patients with or without this variant. In conclusion, the p.E117G variant appears to represent a benign polymorphism. PFN1 mutations, in general, are rare in ALS and FTLD-TDP patients.

Objective: We performed a genome-wide brain expression study to reveal the underpinnings of diseases linked to a repeat expansion in chromosome 9 open reading frame 72 (C9ORF72). Methods: The genome-wide expression profile was investigated in brain tissue obtained from C9ORF72 expansion carriers (n = 32), patients without this expansion (n = 30), and controls (n = 20). Using quantitative real-time PCR, findings were confirmed in our entire pathologic cohort of expansion carriers (n = 56) as well as nonexpansion carriers (n = 31) and controls (n = 20). Results: Our findings were most profound in the cerebellum, where we identified 40 differentially expressed genes, when comparing expansion carriers to patients without this expansion, including 22 genes that have a homeobox (e.g., HOX genes) and/or are located within the HOX gene cluster (top hit: homeobox A5 [HOXA5]). In addition to the upregulation of multiple homeobox genes that play a vital role in neuronal development, we noticed an upregulation of transthyretin (TTR), an extracellular protein that is thought to be involved in neuroprotection. Pathway analysis aligned with these findings and revealed enrichment for gene ontology processes involved in (anatomic) development (e.g., organ morphogenesis). Additional analyses uncovered that HOXA5 and TTR levels are associated with C9ORF72 variant 2 levels as well as with intron-containing transcript levels, and thus, disease-related changes in those transcripts may have triggered the upregulation of HOXA5 and TTR. Conclusions: In conclusion, our identification of genes involved in developmental processes and neuroprotection sheds light on potential compensatory mechanisms influencing the occurrence, presentation, and/or progression of C9ORF72-related diseases.

Progranulin (GRN) loss-of-function mutations leading to progranulin protein (PGRN) haploinsufficiency are prevalent genetic causes of frontotemporal dementia. Reports also indicated PGRN-mediated neuroprotection in models of Alzheimer's and Parkinson's disease; thus, increasing PGRN levels is a promising therapeutic for multiple disorders. To uncover novel PGRN regulators, we linked whole-genome sequence data from 920 individuals with plasma PGRN levels and identified the prosaposin (PSAP) locus as a new locus significantly associated with plasma PGRN levels. Here we show that both PSAP reduction and overexpression lead to significantly elevated extracellular PGRN levels. Intriguingly, PSAP knockdown increases PGRN monomers, whereas PSAP overexpression increases PGRN oligomers, partly through a protein–protein interaction. PSAP-induced changes in PGRN levels and oligomerization replicate in human-derived fibroblasts obtained from a GRN mutation carrier, further supporting PSAP as a potential PGRN-related therapeutic target. Future studies should focus on addressing the relevance and cellular mechanism by which PGRN oligomeric species provide neuroprotection., Increasing progranulin (PGRN) levels is a promising approach for treating frontotemporal dementia and other neurodegenerative diseases. Here Nicholson et al. show that the prosaposin (PSAP) locus is associated with plasma PGRN levels and demonstrate that PSAP can alter PGRN levels and its oligomerization.

Amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD) are overlapping, fatal neurodegenerative disorders in which the molecular and pathogenic basis remains poorly understood. Ubiquitinated protein aggregates, of which TDP-43 is a major component, are a characteristic pathological feature of most ALS and FTD patients. Here we use genome-wide linkage analysis in a large ALS/FTD kindred to identify a novel disease locus on chromosome 16p13.3. Whole-exome sequencing identified a CCNF missense mutation at this locus. Interrogation of international cohorts identified additional novel CCNF variants in familial and sporadic ALS and FTD. Enrichment of rare protein-altering CCNF variants was evident in a large sporadic ALS replication cohort. CCNF encodes cyclin F, a component of an E3 ubiquitin–protein ligase complex (SCFCyclin F). Expression of mutant CCNF in neuronal cells caused abnormal ubiquitination and accumulation of ubiquitinated proteins, including TDP-43 and a SCFCyclin F substrate. This implicates common mechanisms, linked to protein homeostasis, underlying neuronal degeneration., Ian Blair and colleagues use genome-wide linkage analysis and whole exome sequencing to identify mutations in the CCNF gene in large cohorts of amyotrophic lateral sclerosis and frontotemporal dementia patients. In addition to validating the mutations in international cohorts, the authors also show that mutant CCNF gene product affects ubiquitination and protein degradation in cultured cells.

Neurodegenerative diseases are often characterized by the presence of aggregates of misfolded proteins. TDP-43 is a major component of these aggregates in amyotrophic lateral sclerosis (ALS), but has also been observed in Alzheimer's (AD) and Parkinson's Diseases (PD). In addition, mutations in the TARDBP gene, encoding TDP-43, have been found to be a significant cause of familial ALS (FALS). All mutations, except for one, have been found in exon 6. To confirm this observation in ALS and to investigate whether TARDBP may play a role in the pathogenesis of AD and PD, we screened for mutations in exon 6 of the TARDBP gene in three cohorts composed of 376 AD, 463 PD (18% familial PD) and 376 ALS patients (50% FALS). We found mutations in ∼ 7% of FALS and ∼0.5% of sporadic ALS (SALS) patients, including two novel mutations, p.N352T and p.G384R. In contrast, we did not find TARDBP mutations in our cohort of AD and PD patients. These results suggest that mutations in TARDBP are not a significant cause of AD and PD.

RNA processing is a tightly regulated, highly complex pathway which includes RNA transcription, pre-mRNA splicing, editing, transportation, translation, and degradation of RNA. Over the past few years, several RNA processing genes have been shown to be mutated or genetically associated with amyotrophic lateral sclerosis (ALS), including the RNA-binding proteins TDP-43 and FUS/TLS. These findings suggest that RNA processing may represent a common pathogenic mechanism involved in development of ALS. In this review, we will discuss six ALS-related, RNA processing genes including their discovery, function, and commonalities.

Perinatal white matter injury, or periventricular leukomalacia (PVL), is the most common cause of brain injury in premature infants and is the leading cause of cerebral palsy. Despite increasing numbers of surviving extreme premature infants and associated long-term neurological morbidity, our understanding and treatment of PVL remains incomplete. inflammation or ischemia/hypoxia-based rodent models, although immensely valuable, are largely restricted to reproducing short-term features of up to 3 weeks after injury. Given the long-term sequelae of PVL, there is a need for subchronic models that will enable testing of putative neuroprotective therapies. Here, we report long term characterization of a neonatal inflammation-induced rat model of PVL. We show bilateral ventriculomegaly, inflammnation, reactive astrogliosts, injury to pre-oligodendrocytes, and neuronal loss 8 weeks after injury. We demonstrate neuroprotective effects of oligodendrocyte precursor cell transplantation. Our findings present a subchronic model of PVL and highlight the tissue protective effects of of oligodendrocyte precursor cell transplants that demonstrate the potential of cell-based therapy for PVL. (Am J Pathol 2009, 175:2332-2342; DOI: 10.2353/ajpath.2009.090051)

C9orf72 mutations are the most common cause of amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD). Dipeptide repeat proteins (DPRs) produced by unconventional translation of the C9orf72 repeat expansions cause neurodegeneration in cell culture and in animal models. We performed two unbiased screens in Saccharomyces cerevisiae and identified potent modifiers of DPR toxicity, uncovering karyopherins and effectors of Ran-mediated nucleocytoplasmic transport, providing insight into potential disease mechanisms and therapeutic targets.

Increasing evidence suggests that defective RNA processing contributes to the development of amyotrophic lateral sclerosis (ALS). This may be especially true for ALS caused by a repeat expansion in C9orf72 (c9ALS), in which the accumulation of RNA foci and dipeptide-repeat proteins are expected to modify RNA metabolism. We report extensive alternative splicing (AS) and alternative polyadenylation (APA) defects in the cerebellum of c9ALS subjects (8,224 AS and 1,437 APA), including changes in ALS-associated genes (for example, ATXN2 and FUS), and in subjects with sporadic ALS (sALS; 2,229 AS and 716 APA). Furthermore, heterogeneous nuclear ribonucleoprotein H (hnRNPH) and other RNA-binding proteins are predicted to be potential regulators of cassette exon AS events in both c9ALS and sALS. Co-expression and gene-association network analyses of gene expression and AS data revealed divergent pathways associated with c9ALS and sALS.

Repeat expansions in chromosome 9 open reading frame 72 (C9ORF72) are an important cause of both motor neuron disease (MND) and frontotemporal dementia (FTD). Currently, little is known about factors that could account for the phenotypic heterogeneity detected in C9ORF72 expansion carriers. In this study, we investigated 4 genes that could represent genetic modifiers: ataxin-2 (ATXN2), non-imprinted in Prader-Willi/Angelman syndrome 1 (NIPA1), survival motor neuron 1 (SMN1), and survival motor neuron 2 (SMN2). Assessment of these genes, in a unique cohort of 331 C9ORF72 expansion carriers and 376 control subjects, revealed that intermediate repeat lengths in ATXN2 possibly act as disease modifier in C9ORF72 expansion carriers; no evidence was provided for a potential role of NIPA1, SMN1, or SMN2. The effects of intermediate ATXN2 repeats were most profound in probands with MND or FTD/MND (2.1% vs. 0% in control subjects, p = 0.013), whereas the frequency in probands with FTD was identical to control subjects. Though intermediate ATXN2 repeats were already known to be associated with MND risk, previous reports did not focus on individuals with clear pathogenic mutations, such as repeat expansions in C9ORF72. Based on our present findings, we postulate that intermediate ATXN2 repeat lengths may render C9ORF72 expansion carriers more susceptible to the development of MND; further studies are needed, however, to validate our findings. (C) 2014 Elsevier Inc. All rights reserved.

Amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD) are complex neurodegenerative disorders that can be either sporadic or familial and can overlap clinically and pathologically. We present the first Central-Eastern European family with ALS-FTD syndrome due to a C9ORF72 repeat expansion.We studied a family consisting of 37 family members, 6 of whom were genetically evaluated for C9ORF72 expansions. Family members were evaluated clinically, by history, and by chart review.Overall, 5 generations of the family were studied, and 6 affected family members were identified. All affected members were females and had a different clinical presentation, which was ALS, FTD or both. Among the genetically evaluated subjects, 5 carried a C9ORF72 expansion; 4 of these individuals remain clinically unaffected.Our report reveals that the hexanucleotide repeat expansion of C9ORF72, which is the most common genetic cause of ALS-FTD complex disorder, is also present in Central-Eastern Europe. Further studies are needed to assess the frequency of this expansion in the Polish population with familial as well as sporadic ALS, FTD and the ALS-FTD complex disorder.

Frontotemporal dementia (FTD) and amyotrophic lateral sclerosis (ALS) are devastating neurodegenerative disorders with clinical, genetic, and neuropathological overlap. Hexanucleotide (GGGGCC) repeat expansions in a noncoding region of C9ORF72 are the major genetic cause of FTD and ALS (c9FTD/ALS). The RNA structure of GGGGCC repeats renders these transcripts susceptible to an unconventional mechanism of translation repeat-associated non-ATG (RAN) translation. Antibodies generated against putative GGGGCC repeat RAN-translated peptides (anti-C9RANT) detected high molecular weight, insoluble material in brain homogenates, and neuronal inclusions throughout the CNS of c9FTD/ALS cases. C9RANT immunoreactivity was not found in other neurodegenerative diseases, including GAG repeat disorders, or in peripheral tissues of c9FTD/ALS. The specificity of C9RANT for c9FTD/ALS is a potential biomarker for this most common cause of FTD and ALS. These findings have significant implications for treatment strategies directed at RAN-translated peptides and their aggregation and the RNA structures necessary for their production.

In 2012, researchers published extensively on the genetic and clinicopathological characterization of patients with the newly discovered C9ORF72 repeat expansions, which cause amyotrophic lateral sclerosis (ALS) and frontotemporal dementia. Novel ALS-linked genes and genetic modifiers were identified through screening in animal models and patients.

Previously, we have reported amyotrophic lateral sclerosis (ALS) families with multiple mutations in major ALS-associated genes. These findings provided evidence for an oligogenic basis of ALS. In our present study, we screened a cohort of 755 sporadic ALS patients, 111 familial ALS patients (97 families), and 765 control subjects of Dutch descent for mutations in vesicle-associated membrane protein B (VAPB). We have identified 1 novel VAPB mutation (p.V234I) in a familial ALS patient known to have a chromosome 9 open reading frame 72 (C9orf72) repeat expansion. This p.V234I mutation was absent in control subjects, located in a region with high evolutionary conservation, and predicted to have damaging effects. Taken together, these findings provide additional evidence for an oligogenic basis of ALS. (C) 2012 Elsevier Inc. All rights reserved

Item does not contain fulltext Optineurin (OPTN) mutations have been reported in a cohort of Japanese patients with familial (FALS) and sporadic (SALS) amyotrophic lateral sclerosis. In Caucasian patients, OPTN mutations have been identified in FALS patients, but were not detected in a cohort of 95 SALS patients. Moreover, single nucleotide polymorphisms (SNPs) in OPTN that could raise amyotrophic lateral sclerosis (ALS) susceptibility have not been investigated. Therefore, we screened a large Dutch cohort of 1191 patients with SALS, 94 patients with FALS, and 1415 control subjects for mutations and SNPs in OPTN. We identified 1 novel nonsense mutation (Q165X) and 1 unreported missense mutation (Q454E) in individual SALS patients. These patients demonstrated rapid disease progression with an average survival of 24.5 months. No heterozygous or homozygous OPTN mutations were identified in our cohort of FALS patients. SNP analysis did not reveal significant differences between ALS patients and control subjects. Therefore, variations in OPTN appear to be a rare cause of rapidly progressive SALS in the Netherlands. 01 mei 2012

Item does not contain fulltext Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disorder with a substantial heritable component. In pedigrees affected by its familial form, incomplete penetrance is often observed. We hypothesized that this could be caused by a complex inheritance of risk variants in multiple genes. Therefore, we screened 111 familial ALS (FALS) patients from 97 families, and large cohorts of sporadic ALS (SALS) patients and control subjects for mutations in TAR DNA-binding protein (TARDBP), fused in sarcoma/translated in liposarcoma (FUS/TLS), superoxide dismutase-1 (SOD1), angiogenin (ANG) and chromosome 9 open reading frame 72 (C9orf72). Mutations were identified in 48% of FALS families, 8% of SALS patients and 0.5% of control subjects. In five of the FALS families, we identified multiple mutations in ALS-associated genes. We detected FUS/TLS and TARDBP mutations in combination with ANG mutations, and C9orf72 repeat expansions with TARDBP, SOD1 and FUS/TLS mutations. Statistical analysis demonstrated that the presence of multiple mutations in FALS is in excess of what is to be expected by chance (P = 1.57 x 10(-7)). The most compelling evidence for an oligogenic basis was found in individuals with a p.N352S mutation in TARDBP, detected in five FALS families and three apparently SALS patients. Genealogical and haplotype analyses revealed that these individuals shared a common ancestor. We obtained DNA of 14 patients with this TARDBP mutation, 50% of whom had an additional mutation (ANG, C9orf72 or homozygous TARDBP). Hereby, we provide evidence for an oligogenic aetiology of ALS. This may have important implications for the interpretation of whole exome/genome experiments designed to identify new ALS-associated genes and for genetic counselling, especially of unaffected family members.

Item does not contain fulltext Abstract Our objective was to investigate TDP-43 plasma levels in patients with amyotrophic lateral sclerosis (ALS). TDP-43 has been identified as a major component of protein inclusions in the brain of patients with ALS; mutations in the corresponding gene (TARDBP) have also been identified. Although increased TDP-43 levels have been reported in the cerebrospinal fluid, plasma levels have not yet been assessed in patients with ALS. TDP-43 levels were quantified by sandwich ELISA in plasma of 219 patients and 100 controls. In addition, we sequenced exon 6 of TARDBP, and performed longitudinal TDP-43 plasma measurements in a subset of patients. Results showed that TDP-43 plasma levels were significantly increased in patients with ALS (p = 0.023) and we found a positive correlation with age in patients and controls. Longitudinal measurements of TDP-43 plasma levels showed an increase in only one patient, with stable levels in five others. Three TARDBP variations were identified in the ALS group (1.7%), but the association with TDP-43 plasma levels was ambiguous. In conclusion, our data indicate that TDP-43 plasma levels may have potential as a marker for ALS. A genotype-phenotype relationship could not, however, be established in this cohort. 01 september 2012

Contains fulltext : 107990.pdf (Publisher’s version ) (Open Access) Progressive muscular atrophy (PMA) and amyotrophic lateral sclerosis (ALS) are devastating motor neuron diseases (MNDs), which result in muscle weakness and/or spasticity. We compared mutation frequencies in genes known to be associated with MNDs between patients with apparently sporadic PMA and ALS. A total of 261 patients with adult-onset sporadic PMA, patients with sporadic ALS, and control subjects of Dutch descent were obtained at national referral centers for neuromuscular diseases in The Netherlands. Sanger sequencing was used to screen these subjects for mutations in the coding regions of superoxide dismutase-1 (SOD1), angiogenin (ANG), fused in sarcoma/translated in liposarcoma (FUS/TLS), TAR DNA-binding protein 43 (TARDBP), and multivesicular body protein 2B (CHMP2B). In our cohort of PMA patients we identified two SOD1 mutations (p.D90A, p.I113T), one ANG mutation (p.K17I), one FUS/TLS mutation (p.R521H), one TARDBP mutation (p.N352S), and one novel CHMP2B mutation (p.R69Q). The mutation frequency of these genes was similar in sporadic PMA (2.7%) and ALS (2.0%) patients, and therefore, our findings demonstrate a genetic overlap between apparently sporadic PMA and ALS.

Mutations in the valosin-containing protein (VCP) gene were recently reported to be the cause of 1%-2% of familial amyotrophic lateral sclerosis (ALS) cases. VCP mutations are known to cause inclusion body myopathy (IBM) with Paget's disease (PDB) and frontotemporal dementia (FTD). The presence of VCP mutations in patients with sporadic ALS, sporadic ALS-FTD, and progressive muscular atrophy (PMA), a known clinical mimic of inclusion body myopathy, is not known. To determine the identity and frequency of VCP mutations we screened a cohort of 93 familial ALS, 754 sporadic ALS, 58 sporadic ALS-FTD, and 264 progressive muscular atrophy patients for mutations in the VCP gene. Two nonsynonymous mutations were detected; 1 known mutation (p.R159H) in a patient with familial ALS with several family members suffering from FTD, and 1 mutation (p.I114V) in a patient with sporadic ALS. Conservation analysis and protein prediction software indicate the p.I114V mutation to be a rare benign polymorphism. VCP mutations are a rare cause of familial ALS. The role of VCP mutations in sporadic ALS, if present, appears limited. (C) 2012 Elsevier Inc. All rights reserved

Optineurin (OPTN) mutations have been reported in a cohort of Japanese patients with familial (PALS) and sporadic (SALS.) amyotrophic lateral sclerosis. In Caucasian patients, OPTN mutations have been identified in PALS patients, but were not detected in a cohort of 95 SALS patients. Moreover, single nucleotide polymorphisms (SNPs) in OPTN that could raise amyotrophic lateral sclerosis (ALS) susceptibility have not been investigated. Therefore, we screened a large Dutch cohort of 1191 patients with SALS, 94 patients with PALS, and 1415 control subjects for mutations and SNPs in OPTN. We identified 1 novel nonsense mutation (Q165X) and 1 unreported missense mutation (Q454E) in individual SALS patients. These patients demonstrated rapid disease progression with an average survival of 24.5 months. No heterozygous or homozygous OPTN mutations were identified in our cohort of FALS patients. SNP analysis did not reveal significant differences between ALS patients and control subjects. Therefore, variations in OPTN appear to be a rare cause of rapidly progressive SALS in the Netherlands. (C) 2012 Published by Elsevier Inc

Three clustered, homologous paraoxonase genes (PON1, PON2 and PON3) have roles in preventing lipid oxidation and detoxifying organophosphates. Recent reports describe a genetic association between the PON genes and sporadic amyotrophic lateral sclerosis (ALS). We now report that in genomic DNA from individuals with familial and sporadic ALS we have identified at least seven PON gene mutations that are predicted to alter PON function.

In 2012, researchers published extensively on the genetic and clinicopathological characterization of patients with the newly discovered C90RF72 repeat expansions, which cause amyotrophic lateral sclerosis (ALS) and frontotemporal dementia. Novel ALS-linked genes and genetic modifiers were identified through screening in animal models and patients. Rademakers, R. & van Blitterswijk, M. Nat. Rev. Neurol. 9, 63-64 (2013); published online 15 January 2013; doi:10.1038/nrneurol.2012.276

Item does not contain fulltext 01 juni 2012

Item does not contain fulltext Mutations in TAR DNA-binding protein (TARDBP) are associated with heterogenic phenotypes, including amyotrophic lateral sclerosis, frontotemporal dementia, and Parkinson's disease. In this study, we investigated the presence of TARDBP mutations in a cohort of 429 Dutch patients with Parkinson's disease. Though we detected 1 silent mutation, p.S332S, no missense mutations were present in our cohort. Our findings, therefore, demonstrate that TARDBP mutations do not appear to contribute to the pathogenesis of Parkinson's disease in The Netherlands.

Figure S1. Repeat-containing plasmids have a large repeat size distribution. Figure S2. Sanger sequencing confirms the SCA36 repeat plasmid contains at least 37 repeats. Figure S3. Individual Sequel and MinION read(s) across the C9orf72 repeat region aligned to the reference genome and hand curated. Data S1. RS II consensus sequence in the C9-774 repeat region is 99.77% accurate, when compared to the plasmid reference sequence. Data S2. MinION consensus sequence in the C9-774 repeat region is 26.55% accurate, when compared to the plasmid reference sequence. Data S3. MinION read covering the non-pathogenic allele. Data S4. Sequel read covering the non-pathogenic allele. Data S5. Sequel read that did not extend through repeat, but contains approximately 30 repeats. Data S6. Sequel read covering approximately 69 repeats. Data S7. Sequel read that did not extend through the repeat, but contains approximately 912 repeats. Data S8. Sequel read covering 1324-repeat allele. Data S9. PacBio Sequel consensus sequence by Long Amplicon Analysis (LAA2). Data S10. Plasmid backbones used to separate reads. Data S11. Sequences adjacent to the C9orf72 repeat region used to identify on-target reads from the PacBio No-Amp Targeted Sequencing approach. (DOCX 3982 kb)

Figure S1. Repeat-containing plasmids have a large repeat size distribution. Figure S2. Sanger sequencing confirms the SCA36 repeat plasmid contains at least 37 repeats. Figure S3. Individual Sequel and MinION read(s) across the C9orf72 repeat region aligned to the reference genome and hand curated. Data S1. RS II consensus sequence in the C9-774 repeat region is 99.77% accurate, when compared to the plasmid reference sequence. Data S2. MinION consensus sequence in the C9-774 repeat region is 26.55% accurate, when compared to the plasmid reference sequence. Data S3. MinION read covering the non-pathogenic allele. Data S4. Sequel read covering the non-pathogenic allele. Data S5. Sequel read that did not extend through repeat, but contains approximately 30 repeats. Data S6. Sequel read covering approximately 69 repeats. Data S7. Sequel read that did not extend through the repeat, but contains approximately 912 repeats. Data S8. Sequel read covering 1324-repeat allele. Data S9. PacBio Sequel consensus sequence by Long Amplicon Analysis (LAA2). Data S10. Plasmid backbones used to separate reads. Data S11. Sequences adjacent to the C9orf72 repeat region used to identify on-target reads from the PacBio No-Amp Targeted Sequencing approach. (DOCX 3982 kb)