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Amyotrophic Lateral Sclerosis (ALS) is a fatal neurodegenerative disease caused by a complex interaction of genetic and environmental factors. Recently, a polymorphic intronic CA repeat in STMN2 gene has been proposed as risk factor for ALS. The presence of long/long CA genotype, especially if one allele had 24 CA, was reported to be significantly associated with the disease in a cohort of sporadic ALS patients. We tested an Italian cohort of 366 ALS patients and 353 healthy controls and we found no association between CA length and ALS risk.

Amyotrophic Lateral Sclerosis (ALS) is a fatal neurodegenerative disease caused by a complex interaction of genetic and environmental factors. Recently, a polymorphic intronic CA repeat in

In the last few years, NEK1 has been identified as a new gene related to amyotrophic lateral sclerosis (ALS). Loss-of-function variants have been mostly described, although several missense variants exist, which pathogenic relevance remains to be established. We attempted to determine the contribution of NEK1 gene in an Italian cohort of 531 sporadic and familial amyotrophic lateral sclerosis (ALS) patients applying massive parallel sequencing technologies. We filtered results of NEK1 gene and identified 20 NEK1 rare variants (MAF

BackgroundKoolen-de Vries syndrome (KdVS) is a multisystem neurodevelopmental disorder caused by 17q21.31 deletions or mutations in KANSL1. It was mainly described in children.MethodsA retrospective study on 9 subjects aged 19–45 years and revision of 18 literature patients, with the purpose to get insights into the phenotypic evolution with time, and into the clinical manifestations in adulthood.ResultsSeven patients had a 17q21.31 deletion and two a point mutation in KANSL1. All had intellectual disability, which was mild in five (56%) and moderate in four (44%). Epilepsy was diagnosed in four subjects (44%), with onset from 1 to 7 years and full remission before 9 years in 3/4 patients. Scoliosis affected seven individuals (77.7%) and it was substantially stable with age in 5/7 patients, allowing for simple daily activities. Two subjects had severely progressive scoliosis, which was surgically corrected. Overweight or true obesity did occur after puberty in six patients (67%). Behaviour abnormalities were recorded in six patients (67%). The facial phenotype slightly evolved with time to include thick eyebrows, elongated nose and pronounced pointed chin. Despite behaviour abnormalities, happy disposition and sociable attitudes were common. Half of patients had fluent language and were good at writing and reading. Rich language, although limited to single words or short sentences, and very limited or absent skills in writing and reading were observed in the remaining patients. Autonomy in daily activities and personal care was usually limited.ConclusionsDistinctive features in adult KdVS subjects include intellectual disability, overweight/obesity, behaviour abnormalities with preserved social interest, ability in language, slight worsening of the facial phenotype and no seizures.

Amyotrophic lateral sclerosis is a neurodegenerative disease characterized by the degeneration of motor neurons. There is no treatment for this disease that affects the ability to move, eat, speak and finally breathe, causing death. In an Italian family, a heterozygous pathogenic missense variant has been previously discovered in Exon 6 of the gene TARDBP encoding the TAR DNA-binding protein 43 protein. Here, we developed a potential therapeutic tool based on allele-specific small interfering RNAs for familial amyotrophic lateral sclerosis with the heterozygous missense mutation c.1127G>A. We designed a small interfering RNA that was able to diminish specifically the expression of the exogenous Green Fluorescent Protein (TAR DNA-binding protein 43G376D mutant protein) in HEK-293T cells but not that of the Green Fluorescent Protein (TAR DNA-binding protein 43 wild-type). Similarly, this small interfering RNA silenced the mutated allele in fibroblasts derived from patients with amyotrophic lateral sclerosis but did not silence the wild-type gene in control fibroblasts. In addition, we established that silencing the mutated allele was able to strongly reduce the pathological cellular phenotypes induced by TAR DNA-binding protein 43G376D expression, such as the presence of cytoplasmic aggregates. Thus, we have identified a small interfering RNA that could be used to silence specifically the mutated allele to try a targeted therapy for patients carrying the p.G376D TAR DNA-binding protein 43 mutation.

Mutations in FUS and TBK1 often cause aggressive early-onset amyotrophic lateral sclerosis (ALS) or a late-onset ALS and/or frontotemporal dementia (FTD) phenotype, respectively. Co-occurrence of mutations in two or more Mendelian ALS/FTD genes has been repeatedly reported. However, little is known how two pathogenic ALS/FTD mutations in the same patient interact to shape the final phenotype. We screened 28 ALS patients with a known FUS mutation by whole-exome sequencing and targeted evaluation for mutations in other known ALS genes followed by genotype–phenotype correlation analysis of FUS/TBK1 double-mutant patients. We report on new and summarize previously published FUS and TBK1 double-mutant ALS/FTD patients and their families. We found that, within a family, mutations in FUS cause ALS while TBK1 single mutations are observed in FTD patients. FUS/TBK1 double mutations manifested as ALS and without a manifest difference regarding age at onset and disease duration when compared to FUS single-mutant individuals. In conclusion, TBK1 and FUS variants do not seem to interact in a simple additive way. Rather, the phenotype of FUS/TBK1 double-mutant patients appears to be dominated by the FUS mutation.

Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disease that selectively affects motor neurons. In 20% of cases, ALS appears in comorbidity with frontotemporal dementia (FTD). We generated patient-derived-induced Pluripotent Stem Cells (iPSCs), from an ALS/FTD patient. The patient had a familial form of the disease and a missense variant in TARDBP gene. We used an established protocol based on Sendai virus to reprogram fibroblasts. We confirmed the stemness and the pluripotency of the iPSC clones, thus generating embryoid bodies. We believe that the iPSC line carrying a TARDBP mutation could be a valuable tool to investigate TDP-43 proteinopathy linked to ALS.

Amyotrophic lateral sclerosis (ALS) is a devastating neurodegenerative disease affecting upper and lower motor neurons. We generated patient-derived-induced Pluripotent Stem Cells (iPSCs), from an ALS patient affected by an early-onset and aggressive form of the disease, carrying a missense pathogenic variant in FUS gene. We reprogrammed somatic cells using an established Sendai virus protocol and we obtained clones of iPSC. We confirmed their stemness and further generated embryoid bodies, showing their potential of differentiating in all three germ layers. This iPSC line, carrying a pathogenic FUS variant, is a valuable tool to deeply investigate pathogenic mechanisms leading to ALS.

Background An increasing number of studies evidences that amyotrophic lateral sclerosis (ALS) is characterized by extensive alterations in different cell types and in different regions besides the CNS. We previously reported the upregulation in ALS models of a gene called fibroblast-specific protein-1 or S100A4, recognized as a pro-inflammatory and profibrotic factor. Since inflammation and fibrosis are often mutual-sustaining events that contribute to establish a hostile environment for organ functions, the comprehension of the elements responsible for these interconnected pathways is crucial to disclose novel aspects involved in ALS pathology. Methods Here, we employed fibroblasts derived from ALS patients harboring the C9orf72 hexanucleotide repeat expansion and ALS patients with no mutations in known ALS-associated genes and we downregulated S100A4 using siRNA or the S100A4 transcriptional inhibitor niclosamide. Mice overexpressing human FUS were adopted to assess the effects of niclosamide in vivo on ALS pathology. Results We demonstrated that S100A4 underlies impaired autophagy and a profibrotic phenotype, which characterize ALS fibroblasts. Indeed, its inhibition reduces inflammatory, autophagic, and profibrotic pathways in ALS fibroblasts, and interferes with different markers known as pathogenic in the disease, such as mTOR, SQSTM1/p62, STAT3, α-SMA, and NF-κB. Importantly, niclosamide in vivo treatment of ALS-FUS mice reduces the expression of S100A4, α-SMA, and PDGFRβ in the spinal cord, as well as gliosis in central and peripheral nervous tissues, together with axonal impairment and displays beneficial effects on muscle atrophy, by promoting muscle regeneration and reducing fibrosis. Conclusion Our findings show that S100A4 has a role in ALS-related mechanisms, and that drugs such as niclosamide which are able to target inflammatory and fibrotic pathways could represent promising pharmacological tools for ALS.

Amyotrophic lateral sclerosis (ALS) is an incurable neurodegenerative condition with phenotypic and genetic heterogeneity. It is characterized by the selective vulnerability and the progressive loss of the neural population. Here, an induced pluripotent stem cell (iPSC) line was generated from dermal fibroblasts of an individual carrying the p.G376D mutation in the TDP-43 protein. Fibroblasts were reprogrammed using non-integrating episomal plasmids. There were no karyotype abnormalities, and iPSCs successfully differentiated into all three germ layers. This cell line may prove useful in the study of the pathogenic mechanisms that underpin ALS syndrome.

BackgroundAn increasing number of studies evidence that amyotrophic lateral sclerosis (ALS) is characterized by extensive alterations in different cell types and in different regions besides the CNS. We previously reported the up-regulation in ALS models of a gene called fibroblast-specific protein (FSP)-1 or S100A4, generally recognized as a pro-inflammatory and profibrotic factor. Since inflammation and fibrosis are often mutual-sustaining events that contribute to establish a hostile environment for organ functioning, the comprehension of the elements responsible for these interconnected pathways is crucial to disclose novel aspects involved in ALS pathology.MethodsHere we employed fibroblasts derived from ALS patients harboring the C9orf72 hexanucleotide repeat expansion and sporadic ALS patients with no mutations in known ALS-associated genes and we downregulated S100A4 using siRNA or the S100A4 transcriptional inhibitor niclosamide. Mice overexpressing human FUS were adopted to assess the effects of niclosamide in vivo on ALS pathology.ResultsWe demonstrated that S100A4 underlies impaired autophagy and a profibrotic phenotype, which characterize ALS fibroblasts. Indeed, its inhibition reduces inflammatory, autophagic and profibrotic pathways in ALS fibroblasts, and to interfere with different markers known as pathogenic in the disease, such as mTOR, SQSTM1/p62, STAT3, α-SMA and NF-κB. Importantly, niclosamide in vivo treatment of ALS-FUS mice reduces the expression of S100A4, α-SMA and PDGFRβ in the spinal cord, as well as gliosis in central and peripheral nervous tissues, together with axonal impairment and displays beneficial effects on muscle atrophy, by promoting muscle regeneration and reducing fibrosis.ConclusionOur findings show that S100A4 has a role in ALS-related mechanisms, and that drugs such as niclosamide that are able to target inflammatory and fibrotic pathways could represent promising pharmacological tools for ALS.

Koolen-de Vries syndrome (KdVS) is a multisystem neurodevelopmental disorder caused by 17q21.31 deletions or mutations inA retrospective study on 9 subjects aged 19-45 years and revision of 18 literature patients, with the purpose to get insights into the phenotypic evolution with time, and into the clinical manifestations in adulthood.Seven patients had a 17q21.31 deletion and two a point mutation inDistinctive features in adult KdVS subjects include intellectual disability, overweight/obesity, behaviour abnormalities with preserved social interest, ability in language, slight worsening of the facial phenotype and no seizures.

BACKGROUND AND PURPOSE: The aim of our study was to describe patients with the p.D12Y variant (previously reported as D11Y) in SOD1 showing heterogeneous clinicopathological features. METHODS: We performed clinical, electrophysiological, magnetic resonance imaging (MRI) and muscle pathology studies in four SOD1 p.D12Y variant-positive patients. RESULTS: The SOD1 p.D12Y clinical manifestations ranged from a benign phenotype characterized by distal distribution of muscular weakness and long survival to classic forms of amyotrophic lateral sclerosis with poor prognosis. Two patients with the distal clinical phenotype showed MRI and muscle pathology alterations indicating a concurrent muscle involvement. In one of these patients significant myopathic changes were associated with rimmed vacuolar pathology. CONCLUSIONS: We expand the clinical spectrum of SOD1 p.D12Y variant, including predominant lower motor neuron forms with long survival and classic forms with aggressive course. Some patients may have concomitant distal myopathy without other explanations. Given clinical, MRI and muscle pathology alterations, SOD1 should be considered in the differential diagnosis of molecularly undefined distal myopathies with rimmed vacuoles.

The main hallmark of many forms of familiar and sporadic amyotrophic lateral sclerosis (ALS) is a reduction in nuclear TDP-43 protein and its inclusion in cytoplasmic aggregates in motor neurons. In order to understand which cellular and molecular mechanisms underlie the mislocalization of TDP-43, we examined human skin fibroblasts from two individuals with familial ALS, both with mutations in TDP-43, and two individuals with sporadic ALS, both without TDP-43 mutations or mutations in other ALS related genes. We found that all ALS fibroblasts had a partially cytoplasmic localization of TDP-43 and had reduced cell metabolism as compared to fibroblasts from apparently healthy individuals. ALS fibroblasts showed an increase in global protein synthesis and an increase in 4E-BP1 and rpS6 phosphorylation, which is indicative of mTORC1 activity. We also observed a decrease in glutathione (GSH), which suggests that oxidative stress is elevated in ALS. ERK1/2 activity regulated the extent of oxidative stress and the localization of TDP-43 in the cytoplasm in all ALS fibroblasts. Lastly, ALS fibroblasts showed reduced stress granule formation in response to H2O2 stress. In conclusion, these findings identify specific cellular and molecular defects in ALS fibroblasts, thus providing insight into potential mechanisms that may also occur in degenerating motor neurons.

The development of high-throughput sequencing technologies and screening of big patient cohorts with familial and sporadic amyotrophic lateral sclerosis (ALS) led to the identification of a significant number of genetic variants, which are sometimes difficult to interpret. The American College of Medical Genetics and Genomics (ACMG) provided guidelines to help molecular geneticists and pathologists to interpret variants found in laboratory testing. We assessed the application of the ACMG criteria to ALS-related variants, combining data from literature with our experience. We analyzed a cohort of 498 ALS patients using massive parallel sequencing of ALS-associated genes and identified 280 variants with a minor allele frequency &lt, 1%. Examining all variants using the ACMG criteria, thus considering the type of variant, inheritance, familial segregation, and possible functional studies, we classified 20 variants as &ldquo, pathogenic&rdquo, In conclusion, ALS&rsquo, s genetic complexity, such as oligogenic inheritance, presence of genes acting as risk factors, and reduced penetrance, needs to be considered when interpreting variants. The goal of this work is to provide helpful suggestions to geneticists and clinicians dealing with ALS.

KAT6B sequence variants have been identified in both patients with the Say-Barber-Biesecker-Young-Simpson syndrome (SBBYSS) and in the genitopatellar syndrome (GPS). In SBBYSS, they were reported to affect mostly exons 16-18 of KAT6B, and the predicted mechanism of pathogenesis was haploinsufficiency or a partial loss of protein function. Truncating variants in KAT6B leading to GPS appear to cluster within the proximal portion of exon 18, associated with a dominant-negative effect of the mutated protein, most likely. Although SBBYSS and GPS have been initially considered allelic disorders with distinctive genetic and clinical features, there is evidence that they represent two ends of a spectrum of conditions referable as KAT6B-related disorders. We detected a de novo truncating variant within exon 7 of KAT6B in a 8-year-old female who presented with mild intellectual disability, facial dysmorphisms highly consistent with SBBYSS, and skeletal anomalies including exostosis, that are usually considered component manifestations of GPS. Following the clinical diagnosis driven by the striking facial phenotype, we analyzed the KAT6B gene by NGS techniques. The present report highlights the pivotal role of clinical genetics in avoiding clear-cut genotype-phenotype categories in syndromic forms of intellectual disability. In addition, it further supports the evidence that a continuum exists within the clinical spectrum of KAT6B-associated disorders.

Background Activating pathogenic variants in PIK3CA gene usually occur at a mosaic status and underlie a variety of segmental overgrowth phenotypes. Germline variants in PIK3CA have been rarely reported, described in a total of 12 patients with macrocephaly to date. Clinical and prognostic features of these germline variants have not been described in detail yet. Methods Targeted deep sequencing by custom panel of the 21 genes involved in the PI3K/AKT/mTOR pathway was performed in a 13‐year‐old boy with macrocephaly and physical overgrowth. PI3K/AKT/mTOR pathway analysis was performed in fibroblasts by Western blot. The effects of miransertib (AKT inhibitor) and rapamycin (mTOR inhibitor) were assessed. Results A de novo pathogenic variant (c.1090G>C; p.Gly364Arg) in PIK3CA gene was detected in a non‐mosaic status in peripheral blood cells, buccal smears, and skin fibroblasts. Increased levels of phosphorylated AKT residues were observed in fibroblasts, rescued by miransertib. Conclusion Germline variants in PIK3CA are associated to a mild phenotype characterized by overgrowth, severe macrocephaly, mild intellectual disability, and few dysmorphic features. Investigations of PI3K/AKT/mTOR pathway should be performed in patients with severe macrocephaly and unspecific physical overgrowth. Longitudinal studies to assess prognosis and cancer predisposition are recommended.

Amyotrophic Lateral Sclerosis (ALS) is characterized by the degeneration of upper and lower motor neurons. Clinical heterogeneity is a well-recognized feature of the disease as age of onset, site of onset and the duration of the disease can vary greatly among patients. A number of genes have been identified and associated to familial and sporadic forms of ALS but the majority of cases remains still unexplained. Recent breakthrough discoveries have demonstrated that clinical manifestations associated with ALS-related genes are not circumscribed to motor neurons involvement. In this view, ALS appears to be linked to different conditions over a continuum or spectrum in which overlapping phenotypes may be identified. In this review, we aim to examine the increasing number of spectra, including ALS/Frontotemporal Dementia and ALS/Myopathies spectra. Considering all these neurodegenerative disorders as different phenotypes of the same spectrum can help to identify common pathological pathways and consequently new therapeutic targets in these incurable diseases.

Variants in tank-binding kinase 1 (TBK1) are responsible for a significant proportion of amyotrophic lateral sclerosis (ALS) cases. In the present study, we analyzed variants in TBK1 extracted by targeted sequencing of 32 genes in a group of 406 Italian patients with ALS. We identified 7 different TBK1 variants in 7 sporadic cases, resulting in a frequency of 1.7%. Three patients had missense variants (p.R357Q, p.R358H, and p.R724C), one patient had a small deletion (p.E618del), and 3 had truncating variants (p.Y482*, p.R229*, and p.N681*). Notably, we found that 4 patients had an additional variant in ALS-related genes: 2 in OPTN and 2 in the 3′UTR region of FUS. By studying an independent group of 7 TBK1-mutated patients previously reported, we found another variant in the 3′UTR region of FUS in one patient. The presence of a second variant in TBK1 variant carriers is an interesting finding that needs to be investigated in larger cohorts of patients. These findings suggest that TBK1 belongs to the category of genes conferring a significantly increased risk but not sufficient to cause disease.

Fibroblasts isolated from an Amyotrophic Lateral Sclerosis (ALS)-patient carrying a mutation in Matrin-3 (p.Q66K -MATR3) gene were reprogrammed to the pluripotency stage by using non-integrating episomal plasmids. We generated the Q66K#44DRM induced pluripotent stem cell (iPSC) line that showed regular karyotype, expressed pluripotency-associated markers and were able to properly differentiate into the three germ layers. The heterozygous missense mutation in the MATR3 gene (p.Q66K), which is associated to ALS disease, was present in the generated iPSC line.Resource tableUnlabelled TableUnique stem cell line identifierCIBIOi001-AAlternative name(s) of stem cell lineQ66K#44DRMInstitutionCIBIO, University of Trento, ItalyContact information of distributorAlessandro Provenzani alessandro.provenzani@unitn.itType of cell lineiPSCs (induced pluripotent stem cells)OriginHumanAdditional origin infoAge:51Sex: MaleEthnicity if known: European, Italian.Cell sourcePatient derived fibroblastsClonalityClonal, clone number 44Method of reprogrammingEpisomal iPSC Reprogramming PlasmidGenetic modificationNOType of modificationSpontaneous mutation (missense)Associated diseaseAmyotrophic Lateral Sclerosis (ALS)Gene/locusMATR3/5q31.2Method of modificationN/AName of transgene or resistanceN/AInducible/constitutive systemN/ADate archived/stock date16/01/2018Cell line repository/bankN/AEthical approvalPatient signed informed consent, number of protocol P/740/CE/2012 released by the ethical committee of the Catholic University School of Medicine

© 2018 Elsevier Inc., 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.

The diverse clinical phenotypes of Wolf–Hirschhorn syndrome (WHS) are the result of haploinsufficiency of several genes, one of which, LETM1, encodes a protein of the mitochondrial inner membrane of uncertain function. Here, we show that LETM1 is associated with mitochondrial ribosomes, is required for mitochondrial DNA distribution and expression, and regulates the activity of an ancillary metabolic enzyme, pyruvate dehydrogenase. LETM1 deficiency in WHS alters mitochondrial morphology and DNA organization, as does substituting ketone bodies for glucose in control cells. While this change in nutrient availability leads to the death of fibroblasts with normal amounts of LETM1, WHS‐derived fibroblasts survive on ketone bodies, which can be attributed to their reduced dependence on glucose oxidation. Thus, remodeling of mitochondrial nucleoprotein complexes results from the inability of mitochondria to use specific substrates for energy production and is indicative of mitochondrial dysfunction. However, the dysfunction could be mitigated by a modified diet—for WHS, one high in lipids and low in carbohydrates.

Several genetic causes have been recently described for neurological diseases, increasing our knowledge of the common pathological mechanisms involved in these disorders. Mutation analysis has shown common causative factors for two major neurodegenerative disorders, ALS and FTD. Shared pathological and genetic markers as well as common neurological signs between these diseases have given rise to the notion of an ALS/FTD spectrum. This overlap among genetic factors causing ALS/FTD and the coincidence of mutated alleles (including causative, risk and modifier variants) have given rise to the notion of an oligogenic model of disease. In this review we summarize major advances in the elucidation of novel genetic factors in these diseases which have led to a better understanding of the common pathogenic factors leading to neurodegeneration.

Craniosynostosis is a heterogeneous condition caused by the premature fusion of cranial sutures, occurring mostly as an isolated anomaly. Pathogenesis of non-syndromic forms of craniosynostosis is largely unknown. In about 15–30% of cases craniosynostosis occurs in association with other physical anomalies and it is referred to as syndromic craniosynostosis. Syndromic forms of craniosynostosis arise from mutations in genes belonging to the Fibroblast Growth Factor Receptor (FGFR) family and the interconnected molecular pathways in most cases. However it can occur in association with other gene variants and with a variety of chromosome abnormalities as well, usually in association with intellectual disability (ID) and additional physical anomalies. Evaluating the molecular properties of the genes undergoing intragenic mutations or copy number variations (CNVs) along with prevalence of craniosynostosis in different conditions and animal models if available, we made an attempt to define two distinct groups of unusual syndromic craniosynostosis, which can reflect direct effects of emerging new candidate genes with roles in suture homeostasis or a non-specific phenotypic manifestation of pleiotropic genes, respectively. RASopathies and 9p23p22.3 deletions are reviewed as examples of conditions in the first group. In particular, we found that craniosynostosis is a relatively common component manifestation of cardio-facio-cutaneous (CFC) syndrome. Chromatinopathies and neurocristopathies are presented as examples of conditions in the second group. We observed that craniosynostosis is uncommon on average in these conditions. It was randomly associated with Kabuki, Koolen-de Vries/KANSL1 haploinsufficiency and Mowat–Wilson syndromes and in KAT6B-related disorders. As an exception, trigonocephaly in Bohring-Opitz syndrome reflects specific molecular properties of the chromatin modifier ASXL1 gene. Surveillance for craniosynostosis in syndromic forms of intellectual disability, as well as ascertainment of genomic CNVs by array-CGH in apparently non-syndromic craniosynostosis is recommended, to allow for improvement of both the clinical outcome of patients and the accurate individual diagnosis.

To clarify the possible involvement of intermediate ATXN1 alleles as risk factors for amyotrophic lateral sclerosis (ALS), we tested ATXN1 in a cohort of 1146 Italian ALS patients, previously screened for variants in other ALS genes, and in 529 controls. We detected ATXN1 alleles with ≥33 polyglutamine repeats in 105 of 1146 patients (9.16%) and 29 of 529 controls (5.48%) (p = 0.003). The frequency of ATXN1 alleles with ≥33 polyglutamine repeats was particularly high in the group of ALS patients carrying the C9orf72 expansion (12/59, 20.3%). We confirmed this result in an independent cohort of C9orf72 Italian patients (10/80 cases, 12.5%), thus finding a cumulative frequency of ATXN1 expansion of 15.82% in C9orf72 carriers (p = 2.40E-05). Our results strongly support the hypothesis that ATXN1 could act as a disease risk gene in ALS, mostly in C9orf72 expansion carriers. Further studies are needed to confirm our results and to define the mechanism by which ATXN1 might contribute to neuronal degeneration leading to ALS.

Pitt-Hopkins syndrome is a neurodevelopmental disorder characterized by severe intellectual disability and a distinctive facial gestalt. It is caused by haploinsufficiency of the TCF4 gene. The TCF4 protein has different functional domains, with the NLS (nuclear localization signal) domain coded by exons 7–8 and the bHLH (basic Helix-Loop-Helix) domain coded by exon 18. Several alternatively spliced TCF4 variants have been described, allowing for translation of variable protein isoforms. Typical PTHS patients have impairment of at least the bHLH domain. To which extent impairment of the remaining domains contributes to the final phenotype is not clear. There is recent evidence that certain loss-of-function variants disrupting TCF4 are associated with mild ID, but not with typical PTHS. We describe a frameshift-causing partial gene deletion encompassing exons 4–6 of TCF4 in an adult patient with mild ID and nonspecific facial dysmorphisms but without the typical features of PTHS, and a c.520C > T nonsense variant within exon 8 in a child presenting with a severe phenotype largely mimicking PTHS, but lacking the typical facial dysmorphism. Investigation on mRNA, along with literature review, led us to suggest a preliminary phenotypic map of loss-of-function variants affecting TCF4. An intragenic phenotypic map of loss-of-function variants in TCF4 is suggested here for the first time: variants within exons 1–4 and exons 4–6 give rise to a recurrent phenotype with mild ID not in the spectrum of Pitt-Hopkins syndrome (biallelic preservation of both the NLS and bHLH domains); variants within exons 7–8 cause a severe phenotype resembling PTHS but in absence of the typical facial dysmorphism (impairment limited to the NLS domain); variants within exons 9–19 cause typical Pitt-Hopkins syndrome (impairment of at least the bHLH domain). Understanding the TCF4 molecular syndromology can allow for proper nosology in the current era of whole genomic investigations.

International audience; Objectives: We describe the largest series of patients with TARDBP mutations presenting with frontotemporal dementia (FTD) and review the cases in the literature to precisely characterize FTD diseases associated with this genotype.Methods: The phenotypic characteristics of 29 TARDBP patients, including 10 new French and Dutch cases and 19 reviewed from the literature, were evaluated.Results: The most frequent phenotype was a behavioral variant frontotemporal dementia (bvFTD), but a significant proportion (40%) of our patients had semantic (svFTD) or nonfluent variants (nfvFTD) at onset; and svFTD was significantly more frequent in TARDBP carriers than in other FTD genotypes (p < 0.001). Remarkably, only a minority (40%) of our patients secondarily developed amyotrophic lateral sclerosis (ALS). Two patients carried a homozygous mutation but strikingly different phenotypes (bvFTD and ALS) indicating that homozygosity does not result in a specific phenotype. Earlier age at onset in children than parent's generations, mimicking an apparent “anticipation” (21.8 ± 9.3 years, p = 0.001), and possible reduced penetrance were present in most families.Conclusions: This study enlarges the phenotypic spectrum of TARDBP and will have important clinical implications: (1) FTD can be the only clinical manifestation of TARDBP mutations; (2) Initial language or semantic disorders might be indicative of a specific genotype; (3) Mutations should be searched in all FTD phenotypes after exclusion of major genes, even in the absence of ALS in the proband or in family history; (4) reduced penetrance and clinical variability should be considered to deliver appropriate genetic counseling.

The aim of our study was to analyse the natural history and clinical features of upper motor neuron- dominant (UMN-D) ALS. We studied a large series of sporadic ALS patients admitted in a single referral centre over a 23-year period. UMN-D phenotype was compared with other ALS forms, including classic ALS, flail arm and progressive muscular atrophy. Seven hundred and thirty-four sporadic ALS patients were included of which 163 had UMN-D ALS. The mean age of onset in UMN-D ALS (52 years) was 10 years lower than in classic ALS (61.4 years, p < 0.0001); sex ratio by age groups significantly differed with respect to other phenotypes. The pattern of spread of lower motor neuron signs in UMN-D was characterized by early involvement of upper limb muscles and late impairment of respiratory muscles. Duration of the disease was longer in the UMN-D group (56 months) than in classic ALS (33 months, p < 0.001). The UMN-D phenotype was a strong independent predictor of long survival. In summary, UMN-D ALS showed significant differences in age of onset, sex ratio, pattern of spreading and prognosis with respect to other ALS forms, most probably reflecting biological differences.

Mutations in SQSTM1, encoding for the protein SQSTM1/p62, have been recently reported in 1-3.5% of patients with amyotrophic lateral sclerosis and frontotemporal lobar degeneration (ALS/FTLD). Inclusions positive for SQSTM1/p62 have been detected in patients with neurodegenerative disorders, including ALS/FTLD. In order to investigate the pathogenic mechanisms induced by SQSTM1 mutations in ALS/FTLD, we developed a zebrafish model. Knock-down of the sqstm1 zebrafish ortholog, as well as impairment of its splicing, led to a specific phenotype, consisting of behavioral and axonal anomalies. Here, we report swimming deficits associated with shorter motor neuronal axons that could be rescued by the overexpression of wild-type human SQSTM1. Interestingly, no rescue of the loss-of-function phenotype was observed when overexpressing human SQSTM1 constructs carrying ALS/FTLD-related mutations. Consistent with its role in autophagy regulation, we found increased mTOR levels upon knock-down of sqstm1. Furthermore, treatment of zebrafish embryos with rapamycin, a known inhibitor of the mTOR pathway, yielded an amelioration of the locomotor phenotype in the sqstm1 knock-down model. Our results suggest that loss-of-function of SQSTM1 causes phenotypic features characterized by locomotor deficits and motor neuron axonal defects that are associated with a misregulation of autophagic processes.

Background The 17q21.31 deletion syndrome phenotype can be caused by either chromosome deletions or point mutations in the KANSL1 gene. To date, about 60 subjects with chromosome deletion and 4 subjects with point mutation in KANSL1 have been reported. Prevalence of chromosome deletions compared with point mutations, genotype–phenotype correlations and phenotypic variability have yet to be fully clarified. Methods We report genotype–phenotype correlations in 27 novel subjects with 17q21.31 deletion and in 5 subjects with KANSL1 point mutation , 3 of whom were not previously reported. Results The prevalence of chromosome deletion and KANSL1 mutation was 83% and 17%, respectively. All patients had similar clinical features, with the exception of macrocephaly, which was detected in 24% of patients with the deletion and 60% of those with the point mutation, and congenital heart disease, which was limited to 35% of patients with the deletion. A remarkable phenotypic variability was observed in both categories, mainly with respect to the severity of ID. Cognitive function was within normal parameters in one patient in each group. Craniosynostosis, subependymal heterotopia and optic nerve hypoplasia represent new component manifestations. Conclusions In KANSL1 haploinsufficiency syndrome, chromosome deletions are greatly prevalent compared with KANSL1 mutations. The latter are sufficient in causing the full clinical phenotype. The degree of intellectual disability (ID) appears to be milder than expected in a considerable number of subjects with either chromosome deletion or KANSL1 mutation. Striking clinical criteria for enrolling patients into KANSL1 analysis include speech delay, distinctive facial dysmorphism, macrocephaly and friendly behaviour.

Amyotrophic lateral sclerosis (ALS) is the most common and the best-recognized form of the motor neuron diseases. It is characterized by relentless degeneration of both upper and lower motor neuron...

The chromosome 17q21.31 deletion syndrome is a genomic disorder characterized by highly distinctive facial features, moderate-to-severe intellectual disability, hypotonia and friendly behavior. Here, we show that de novo loss-of-function mutations in KANSL1 (also called KIAA1267) cause a full del(17q21.31) phenotype in two unrelated individuals that lack deletion at 17q21.31. These findings indicate that 17q21.31 deletion syndrome is a monogenic disorder caused by haploinsufficiency of KANSL1.

We investigated a CAG trinucleotide repeat expansion in the ATXN2 gene in amyotrophic lateral sclerosis (ALS). Two new case-control studies, a British dataset of 1474 ALS cases and 567 controls, and a Dutch dataset of 1328 ALS cases and 691 controls were analyzed. In addition, to increase power, we systematically searched PubMed for case-control studies published after 1 August 2010 that investigated the association between ATXN2 intermediate repeats and ALS. We conducted a meta-analysis of the new and existing studies for the relative risks of ATXN2 intermediate repeat alleles of between 24 and 34 CAG trinucleotide repeats and ALS. There was an overall increased risk of ALS for those carrying intermediate sized trinucleotide repeat alleles (odds ratio 3.06 [95% confidence interval 2.37-3.94]; p = 6 × 10(-18)), with an exponential relationship between repeat length and ALS risk for alleles of 29-32 repeats (R(2) = 0.91, p = 0.0002). No relationship was seen for repeat length and age of onset or survival. In contrast to trinucleotide repeat diseases, intermediate ATXN2 trinucleotide repeat expansion in ALS does not predict age of onset but does predict disease risk. publisher: Elsevier articletitle: ATXN2 trinucleotide repeat length correlates with risk of ALS journaltitle: Neurobiology of Aging articlelink: http://dx.doi.org/10.1016/j.neurobiolaging.2016.11.010 content_type: article copyright: © 2016 The Author(s). Published by Elsevier Inc. ispartof: Neurobiology of Aging vol:51 pages:178- ispartof: location:United States status: published

Amyotrophic lateral sclerosis (ALS) is a neurodegenerative disorder characterized by loss of motor neurons in the primary motor cortex, brainstem, and spinal cord. Recently, missense variants in MATR3 were identified in familial and sporadic ALS patients, but very few additional ALS patients have been reported so far. The p.S85C MATR3 variant was previously associated to a different phenotype, namely a distal myopathy associated with dysphagia and dysphonia. Here, we assessed the contribution of MATR3 variants in a cohort of 322 Italian ALS patients. We identified 5 different missense MATR3 variants (p.Q66K, p.G153C, p.E664A, p.S707L, and p.N787S) in 6 patients (1.9%). None of our patients showed signs of myopathy at electrophysiological examination. Muscle biopsy, performed in 2 patients, showed neurogenic changes and normal nuclear staining with anti-matrin 3 antibody. Our results confirm that MATR3 variants are associated with ALS and suggest that they are more frequent in Italian ALS patients. Further studies are needed to elucidate the pathogenic significance of identified variants in sporadic and familial ALS.