We’re excited to announce that NAF will award $940,000 in Ataxia research grants this year! NAF’s Board of Directors approved funding for 25 Ataxia research grants in 2020. Nearly 60 applications were reviewed by a team of the the world’s top Ataxia researchers. They selected the highest quality Ataxia research grant applications for funding. Researchers were awarded funding for the research project term of March 1, 2020 – February 28, 2021. The selected applications spanned the US, Portugal, Spain, Italy, Canada, Poland, and Germany.
Thank you to all the donors who participated in NAF’s Annual Research Drive. Without your support, these studies could not have been funded. We wish all these researchers success as they continue to seek answers that will bring us closer to developing treatments for Ataxia.
Check out more information about each study below. Click the “+” symbol to read the lay summary for that study. Click the “-” symbol to collapse the lay summary for that study.
Research Seed Money Grants
Research Seed Money Grants are available for new and innovative studies that are relevant to the cause, pathogenesis or treatment of the hereditary or sporadic Ataxias. This type of grant is offered primarily as “seed monies” to assist investigators in the early or pilot phase of their studies and as additional support for ongoing investigations on demonstration of need.
Margit Burmeister, PhD
University of Michigan
Identification of a Novel Dominant Pure Ataxia Gene on Chromosome 13
About half of ataxia cases are due to genetic changes. More than 100 genes are known which, when mutated, cause ataxia (“ataxia genes” for short here), and more than 500 genes, when mutated, can cause ataxia as one of many symptoms. Nevertheless, more than half of all individuals with ataxia do not receive a genetic diagnosis when tested, indicating new genes still need to be identified. During the past 20 years, my laboratory has identified about half a dozen novel ataxia genes (ATCAY, KCND3, CWF19L1, ATG5, VPS13D, COQ4), and we also identified mutations in previously known ataxia genes. Knowing the gene is reassuring for affected individuals and can help with family planning. Researcher can identify animal models and the mechanisms of how ataxia emerges. Moreover, in rare cases, gene identification can suggest specific treatments. Recently, we demonstrated for example that a high dose of the over the counter supplement Coenzyme Q10 could much improve the symptoms in two young adults with a form of adolescent ataxia caused by mutations in the COQ4 gene. In another case, identification of mutations in a brain enzyme gene ARSA lead to the diagnosis of metachromatic leukodystrophy (MLD), a fatal disease if not treated early, in a toddler presenting initially with pure ataxia, who recovered fully after the appropriate treatment, a stem cell transplant, was initiated.
Genetic linkage analysis, which nails down the chromosomal region where the ataxia gene is located, played a crucial role in successfully identifying the culprit ataxia gene in most of our success stories. But despite our long-standing experience in genetic ataxia research, there are still families in which the ataxia gene remains to be discovered. The purpose of this proposal is to identify the gene(s) involved in two families in which adult onset pure ataxia is segregating in a dominant fashion. Family 1 consists of two branches, with a total of 11 members, 5 of them affected with ataxia. Family 2 consists of 85 individuals in two branches, with more than 30 individuals recruited. In both families, genetic linkage analysis has narrowed the culprit gene to overlapping segments on chromosome 13. In one of these families, the implicated interval includes a known ataxia gene, FGF14, mutations in which cause SCA27.
Whole exome and whole genome sequencing in 3 affected individuals from both pedigrees have already been performed, using standard analyses, no genetic mutations in the protein coding parts of genes that could cause the disease were identified. However, we know that about a third of all disease-causing mutations are not in the coding part of the genome; hence we propose here to explore the noncoding part of the genome, focusing on the linkage intervals, regions of the genome to which we have located the ataxia gene in these two families.
First, we propose to investigate whether a novel mutation in the region regulating the FGF14 gene may cause SCA27 in these families, as this is the only known ataxia gene in the chromosomal intervals. Previously reported types of mutations in FGF14 have already been excluded. If we identify potential FGF14 variants, we will use cell culture methods to test whether these mutations affect how much FGF14 mRNA is read from the gene.
If we find no evidence for a change near the FGF14 gene, we will next explore our Whole Genome Sequencing (WGS) data for regulatory mutations in all genes within the linked chromosome 13 regions. This is a daunting task, as each human being carries about 10 Million SNPs and several thousand CNVs compared to the reference genome. This task will be helped by focusing on the relatively small linked intervals, and by focusing on only rare or new variants. From this, we expect to be left with just a few thousand variants. Since we have sequenced 3 clearly affected individuals from each family, from different branches, more than 5 generations removed from each other, we anticipate only a handful of these thousands of variants to be in common between all 3 affected individuals. Once these handful of candidate variants have been identified, we will validate them by conventional sequencing in all individuals in the pedigrees. Further biological validation will likely be beyond this seed money, but as in the past, we have often found experts in the proteins and pathways involved who were willing to collaborate.
We are testing these two pedigrees together because linkage indicates that the same gene may be involved, and that may be the case but is not required. It is possible that we identify a regulatory variant in FGF14 in one pedigree and a novel gene in another pedigree, or that both pedigrees have mutations in the same or in different novel genes.
Sara Duarte-Silva, PhD
University of Minho
Studying the effect of the molecular tweezer CLR01 in a mouse model of SCA3
Spinocerebellar ataxia type 3 (SCA3) or Machado-Joseph disease (MJD) is a hereditary late-onset neurological disease. The cause is a mutation in ataxin-3, which causes toxicity by forming aggregates in neuronal cells of the brain. No effective therapies are currently available for this ataxia. Our efforts in the last years have focused on finding therapies that modify SCA3 progression using a well-established mouse model– CMVMJD135, with some promising findings. Many of these molecules enhanced the ability of neurons to cope with the mutated ataxin-3, however, to date, no attempt was made to directly target ataxin-3 aggregation. In this study we aim to test the effect of a compound named CLR01 in the progression of the disease, pathological findings and ataxin-3 aggregation, an important hallmark of the disease. This compound is known as a molecular tweezer (MT) , a type of small molecule drug, which inhibits protein aggregation, which we predict will avoid toxicity to neurons. In fact, molecular tweezers were found to inhibit the formation of large protein aggregates in other neurological diseases, such as Amyotrophic Lateral Sclerosis, Alzheimer’s and Parkinson’s disease and, in some cases, significantly improve the symptoms of the respective animal models. To date, MTs have not been explored in the context of SCA3, and doing so may contribute greatly to the field and represent an exciting therapeutic strategy to follow. Our aims are to analyze the impact of CLR01 on the aggregation process of ataxin-3, motor function and brain pathology of a mouse model of SCA3. If effective, this should help to design prospective clinical trials in SCA3 patients, with the ultimate goal of significantly extending their health span and quality of life.
Taner Akkin, PhD
University of Minnesota – Twin Cities
This grant funded in partnership with the Bob Allison Ataxia Research Center
Label-free optical imaging of atrophy in SCA1 mouse models
We developed an optical imaging device (PS-OCT: polarization sensitive optical coherence tomography), which uses near-infrared light to visualize the brain/cerebellum at micrometer-scale resolution. This type of imaging shows different layers of cerebellar cortex, and is very sensitive to detect the white-matter connections. We reported various cerebellar changes due to progression of ataxia on genetically-engineered mice using ex-vivo imaging of this device. Our long term goal is to develop useful tests for monitoring effectiveness of drugs in living mice. Here, we propose two aims, each of which uses a different version of the optical technique for (1) seeing considerable size of cerebellum in living mouse at 10 micron resolution, and (2) studying the entire cerebellum of sacrificed mice at 2 micron resolution to reveal indications of the disease. Analysis methods will be further developed for visualizing the Purkinje cells, cortical layers, and micro structure and connectivity of the cerebellum. As a result, we will reveal the feasibility of using the optical imaging device for analyzing the pathology, which may provide new insights and opportunities for studying neurodegeneration.
Roger Bannister, PhD
University of Maryland, Baltimore
Using zebrafish to model ataxic CaV2.1 channelopathies
Ca2+ flux into axon terminals via P/Q-type (CaV2.1) Ca2+ channels is the trigger for neurotransmitter release at the neuromuscular junction and many central synapses. Cutting edge whole-exome sequencing techniques have recently led to the identification of a series of new mutations in CaV2.1 that are linked to ataxic disorders with substantial neurodevelopmental components. An in vivo model system that recapitulates locomotor dysfunction is critical to the design of therapeutic approaches to treat this growing family of disorders. For this reason, we propose to establish zebrafish swimming behavior as model system for the ataxic phenotypes and to serve as screening platform for drugs that rescue locomotor function. Since compounds that either enhance or diminish Ca2+ influx via CaV2.1 have been already approved for clinical use, information obtained in the proposed work has the potential to be immediately translatable.
Francesca Maltecca, PhD
Ospedale San Raffaele
Targeting altered proteostasis in cellular and mouse models of AFG3L2-related cerebellar ataxias (SCA28 and SPAX5)
Spinocerebellar ataxia type 28 (SCA28) is a form of juvenile-adult onset, slowly progressive, cerebellar ataxia characterized by unbalanced standing, gait incoordination, ophthalmoparesis and pyramidal signs. Spastic ataxia 5 (SPAX5) is a severe childhood-onset ataxia, associated with spasticity and epilepsy. Both diseases are caused by mutations in the AFG3L2 gene. The encoded protein, AFG3L2, resides in the mitochondrion and controls multiple functional aspects of this organelle. Indeed, AFG3L2 is essential for protein quality control, energy production and regulation of mitochondrial morphology. In agreement, we identified energy failure and altered mitochondrial morphology being key features of SCA28 and SPAX5 pathogenesis, as demonstrated by our studies in cells derived from patients and in mouse models.
We recently discovered the trigger of the pathogenetic cascade leading to neurogeneration in these forms of ataxia. Dysfunction of AFG3L2 causes the toxic accumulation of proteins in mitochondria, which in turn lead to defective energy production and to pathological alteration of mitochondrial morphology. In addition, we found that this mitochondrial proteotoxic stress activates a general stress response in cerebellum of Afg3l2 null mouse models, that could contribute to the pathogenetic process.
In this proposal we aim to specifically target the accumulation of proteins inside mitochondria when AFG3L2 is dysfunctional, to block the consequent pathological cascade of events leading to neurodegeneration. For this purpose, we will employ SCA28 and SPAX5 patient-derived cells and mouse models, that well recapitulate features of these two forms of ataxia.
The results obtained by our studies may provide valuable intervention points for the treatment of SCA28 and SPAX5, for which to date a cure is an unmet need.
Jacques Tremblay, PhD
Using extracellular vesicles to deliver therapeutic proteins for various ataxia
Most hereditary diseases can probably be prevented by gene therapy either 1) the delivery of a normal gene to complement a mutated gene responsible for a recessive disease or 2) by correcting the existing mutated gene responsible for a recessive or a dominant disease with the new CRISPR/Cas9 gene editing technology, which has been developed in the last 6 years. In fact in the last 3 years, this technology has progressed to the extent that it is now possible to modify a specific nucleotide among the 3.2 billion nucleotides present in the human genome. These gene therapy progresses are thus very promising for the various forms of ataxias.
The main problem of gene therapy however was and remains the delivery of the therapeutic agents. Indeed the main viral vector used for gene therapy is the Adeno Associated Virus (AAV), which is faced with two important problems: 1) there is a limit of 4700 nucleotides, which can be delivered by an AAV and 2) the production of AAVs in Good Manufacturing Practice (GMP) conditions required for their administration to patients cost over $500,000. per patient. Thus a cheaper effective delivery method has to be developed. The present project aims to develop the delivery of genes or proteins by extracellular vesicles (EVs) isolated from the patient own blood plasma. The development of this delivery method would increase the safety of the treatment and reduce the cost.
EVs are small vesicles (30 to 150 nm) produced by all cells. They naturally contain proteins and RNAs. They can cross the blood brain barrier to access brain cells, fuse with other cells and deliver their content. There are 1,000,000,000,000,000 EVs per liter of plasma. EVs have already been used to deliver drugs and some proteins but they could also be used to deliver therapeutic genes.
My laboratory has already used the CRISPR/Cas9 technology to modify the dystrophin gene (a potential treatment of Duchenne Muscular Dystrophy) and the frataxin gene (a potential treatment of Friedreich ataxia). In these experiments the therapeutic agents were delivered to mouse models using AAVs. The high cost of GMP AAV production prevented my group from initiating a clinical trial. However, some pharmaceutical companies are currently preparing such trials but the eventual treatment will probably cost over 2 M$ making it unaffordable by most patients. A lower cost solution has to be developed.
We have already developed a good protocol to purify EVs from human plasma for delivery of proteins and genes to cells in culture. We are thus proposing in this grant application the following experiments: 1) We will deliver the frataxin gene to cells of Friedreich patients in culture using EVs and confirm that this increases the expression of frataxin in these cells. 2) We will also deliver the CRISPR/Cas9 components (i.e., the Cas9 protein and an sgRNA) with EVs to a Ai9 mouse model, which has a conditional red fluorescent gene. The genetic modification of that a target gene will produce red fluorescent cells. This will permit us to easily verify that the EVs are able to deliver the Cas9 components to cells in different organs (brain, heart and liver). 3) We will deliver the frataxin gene with EVs to a mouse model of Friedreich ataxia. 4) We will also deliver the components of CRISPR/Cas9 to a mouse model of Friedreich ataxia and verify that we can remove the long GAA repeat responsible for this disease. For experiments 3 and 4, we will verify whether the expression of frataxin is increased and the severity of the coordination symptoms reduced.
The realization of these experiments with the seed money grant from NAF will permit to obtain additional preliminary results, which will favor obtaining a 5 years grant from the Canadian Institute of Health Research (CIHR).
Gal Bitan, PhD
The Regents of the University of California, Los Angeles
Developing Novel Biomarkers for Spinocerebellar Ataxia
Spinocerebellar ataxias (SCAs) are highly debilitating progressive diseases caused by degeneration of nerve cells in the brain and spinal cord. There is no cure for any SCA and symptomatic treatment options are limited.
Developing effective therapy that treats the cause, not just the symptoms, of these diseases is urgently needed. However, a major hurdle for developing such therapy is that we do not have reliable, objective measures for the success of the therapy. When new treatments are evaluated in clinical trials, physicians rely on the clinical symptoms of the patients, which are highly variable. In addition, because the SCAs are rare diseases, recruitment of large numbers of patients is difficult and evaluation of clinical outcomes in a consistent manner across multi-center trials is challenging. To overcome these major obstacles, we need to develop objective measures for evaluation of treatment outcomes, called biomarkers. For example, blood sugar is a biomarker for the state of patients with diabetes and the effects of the treatments they receive. However, there are currently no known biomarkers for SCAs that clinicians and researchers can use. Therefore, discovering such biomarkers is an urgent unmet medical need for patients with SCAs, their families, and their caregivers.
To address this need, we plan to search for biomarkers using a new strategy that has been developed recently in the dementia field. This strategy allows getting an insight into biochemical changes in the brain through a simple blood test. This is achieved by isolating tiny, “nano-size” particles secreted by brain cells that end up in the blood and using sophisticated, ultra-high sensitivity techniques for analyzing their contents, which reflect the original cells in the brain from which these nano-particles came. In this project, we combine the complementary strengths of three different research groups at UCLA. The group of Dr. Brent Fogel, an ataxia specialist and neurogeneticist will collect blood samples from well-diagnosed patients with SCA. The blood samples will then be processed by the group of Dr. Gal Bitan, which has the expertise needed for isolation of the nano-particles originating in the brain. These nano-particles then will be analyzed by the group of Dr. Joe Loo, which specializes in mass-spectrometry, a technique that allows identifying the content of the nano-particles even if the amount of material is minute. Using the combination of state-of-the-art technologies in these three groups, we will search two types of biomarkers: 1) Biomarkers that are common to the different types of SCA but distinguish patients with these diseases from healthy people; and 2) Biomarkers that are unique to most common types of SCA in the US – SCA1, 2, and 3. Our project will lead to discovery and establishment of new biomarkers for SCA, which will be crucially important for developing of therapy for these diseases.
Pedro Fernandez-Funez, PhD
University of Minnesota (Duluth campus)
Genetic and molecular mechanisms mediating congenital deficits in SCA13
Spinocerebellar ataxia type 13 (SCA13) is a rare neurological disorder that shares progressive, late onset degenerative changes in the cerebellum with other SCAs. SCA13 is caused by mutations in a K+ channel, specifically KCNC3. This is one of several channels responsible for ataxias, while mutations in other ion channels are known to cause epilepsy and migraine. SCA13 has interesting distinguishing features from other ataxias and from other channel-inducing disorders. The more relevant features are some mutations with developmental (congenital) effects in the cerebellum, that is, patients born with small cerebella that failed to grow properly. This developmental impact of KCNC3 mutations make them particularly interesting to study since ion channels are known to impact the function of neurons and circuits, but not to have critical developmental functions. Our preliminary data suggest that certain mutations in KCNC3 result in abnormal production and maturation of the K+ channel, resulting in intracellular accumulation in the ER-Golgi and reducing its accumulation at the membrane. This aberrant production of KCNC3 not only causes a loss-of-function that can affect neuronal excitability but also could disrupt the maturation and secretion of other membrane proteins. Thus, we propose that the mechanism leading to the congenital problems in SCA13 are caused by the abnormal processing of KCNC3 mutants “clogging” the maturation and secretion of several membrane proteins, including critical receptors like the Epidermal growth factor receptor (EGFR). Here, we will generate new transgenic flies carrying several congenital KCNC3 mutants to determine whether all of them cause the same developmental perturbations in Drosophila tissues, including eyes, wings and brain neurons. Then, we will investigate novel mechanisms implicated in the disruption of eye development in flies caused by KCNC3-R423H by performing a blind genetic screen. By combining 4,500 strains each carrying a loss-of-function allele for genes highly conserved in humans, we will identify those that rescue or aggravate the eye phenotype. This screen will uncover the genes and pathways implicated in the congenital KCNC3 perturbations, potentially identifying targets for therapeutic intervention. The proposed studies with congenital KCNC3 mutants can also help understand other channel-related neurological disorders.
Dr. Sofia Araújo, PhD
DNA repair failure and the incidence of ataxia in SCAN1 patients
UV-light, cigarrette smoke, environmental pollution and many chemical agents damage our DNA and produce lesions that can lead to cancer and neurodegeneration. In order to cope with the constant damage produced by these sources, our bodies have a natural mechanism that constantly inspects and fixes this DNA damage, the DNA repair machinery. When some parts of this system fail, the people affected may not only develop cancer, but also suffer from various neurodegenerative conditions that may lead to ataxia.
We will investigate the connection between this failure in the DNA repair machinery and its effects on the nervous system during embryonic development that lead to the development of ataxia later in life. To do so, we will use the fruit fly, Drosophila melanogaster, as our model system. Over recent years, the fruit fly has proven to be a great model to study neurodegenerative diseases, like, for instance, Alzheimer’s disease or Friedrich’s ataxia. We have a collection of mutant flies with nervous system defects that we will use to study the connection between DNA repair defects and ataxias. With these mutant fruit flies we can study both the genetics and the biochemistry of nervous system formation in the absence of some of the key players involved in DNA repair. By doing so, we hope to be able to clarify the origin of ataxia in people with spinocerebellar ataxia (SCAN1) whose DNA repair machinery is impaired.
Pioneer SCA Translational Award
The Pioneer SCA Translational Research Award is offered for a research project that will facilitate the development of treatments for Spinocerebellar Ataxia Type 3/Machado Joseph Disease.
Maciej Figiel, PhD
Institute of Bioorganic Chemistry, Polish Academy of Sciences
Allele selective, CAG-targeted RNAi-based strategy to lower mutant polyQ proteins in polyglutamine ataxias
The knowledge about the molecular mechanisms of polyglutamine spinocerebellar ataxias (SCAs) such as SCA3/MJD or SCA7 has been recently advanced. However, developing therapeutic approaches for these diseases remains still a challenge and only symptomatic treatments are offered to patients. Therefore, in this project, we aim to further develop a very promising therapeutic strategy that relies on mutant protein lowering. The molecules which will be used as drug candidates are short fragments of chemically modified ribonucleic acids (RNAs) that elicit therapeutic effects by a mechanism that is called RNA interference. Our potential drugs selectively target the special type of mutation (CAG expansion) in messenger RNA of genes causative to SCA3, SCA7 and other polyQ diseases. In this short-term project, we will examine the safety and efficacy of our approach by using transgenic mice with human mutant genes as a models of SCA3 and SCA7. We will inject the molecules directly in the brain of these mice (and into the eye of SCA7 mice) and subsequently examine if the level of mutant genes in mouse brain cells or eye cells is reduced, i.e. less mutant proteins that directly cause the disease is produced. We will also examine if the lowering of the disease-causing mutant protein can improve molecular signs of the SCA disease which we observe in the brain or retinal cells of these mice. This research effort is a together work of two groups: one working in Strasbourg, France, led by Dr. Yvon Trottier, and the other working in Poznan, Poland, led by Dr. Maciej Figiel. Both groups have considerable achievements in studying SCAs and other polyglutamine diseases and their research experience is complimentary. For instance, transgenic SCA3 and SCA7 mouse models were developed and investigated in Poznan and Strasbourg, respectively, the drugs were developed in Poznan and tested initially in cell culture and mice in Poznan and Strasbourg. Both groups will closely work together to reach the goal of this project which in the long run can be the cure for polyQ SCA diseases.
Young Investigator - SCA Awards
The Young Investigator – SCA Award was created to encourage young clinical and scientific investigators to pursue a career in the field of Spinocerebellar Ataxia research. It is our hope that Ataxia research will be invigorated by the work of young, talented individuals supported by this award.
Alexandra Silva, PhD
Instituto de Biologia Molecular e Celular – IBMC
Fighting Spinocerebellar Ataxia Type 3 at NanoScale
Spinocerebellar ataxia type-3 (SCA3), also known as Machado-Joseph disease (MJD), is a neurodegenerative disorder caused by the expansion of a CAG trinucleotide repeat, codifying for amino acid glutamine, in the gene associated to the disease – Ataxin-3 (ATX3) – leading to the expansion of the polyglutamine (polyQ) tract within the translated protein. This mutation increases Atx3 propensity to aggregate leading to its accumulation as intracellular inclusions in specific neuronal cells leading to neurodegeneration and ultimately to the patients’ death.
Despite the extensive research in the field, no effective MJD therapies have been developed so far and the treatment is merely symptomatic. One of the reasons for this condition is the lack of information on the three-dimensional structure of full-length Atx3, mostly due to its high conformational flexibility, delaying the development of new drugs/molecules specifically designed to bind and block Atx3 aggregation in neuronal cells, preventing MJD.
In this sense, and in the scope of a previous NAF research grant, we identified some conformational nanobodies (Nbs) that specifically bind and stabilize Atx3, with a strong impact on pathogenic Atx3 aggregation.
As a follow-up, and taking advantage of the encouraging results obtained so far, the candidate Nbs will be characterized in atomic detail and modified to improve their potential as leads for the development of effective molecules for future application in targeted therapies against MJD.
The proposed strategy will be critical to improve our understanding of MJD pathogenesis and to develop effective Nbs for targeted therapies to fight this extremely incapacitating disease, improving patients’ quality of life and healthspan.
Jeannette Hübener-Schmid, PhD
University of Tuebingen
Development and Validation of a SIMOA-based mutant Ataxin-3 Immunoassay for biomarker studies in SCA3
Clinical therapeutic studies in the field of Spinocerebellar Ataxia Type 3 (SCA3) often failed because of missing effective measurable primary outcome parameter. The often used clinical score SARA, which represents the personal disease progression over a certain time period, is not sensitive enough for disease modifying clinical trials of short duration. Therefore, there is an urgent need of blood-based marker which represents disease progression and/ or response to therapeutic drugs (like insulin for diabetes). To develop and validate blood-based marker, sensitive techniques are important. There are several techniques available which allow the measurements of protein amounts in peripheral blood to compare the level of the identified marker protein between controls and patients as well as at different disease stages of the same patient. Here we want to adapt one of the known techniques to analyse the amounts of the disease protein in (pre)ataxic SCA3 patients at different disease stages and under therapeutic studies which aim to lower the disease protein. This will pave the way for successful further clinical trials.
Dr. Jennifer Faber, MD
German Center for Neurodegenerative Diseases
Implementation of a deep learning based neuroimaging pipeline for a fast and accurate automated parcellation of cerebellar lobuli and longitudinal volumetry in spinocerebellar ataxias (SCAs)
One of the core alterations in the brain of patients suffering from spinocerebellar ataxia is the decrease of cerebellar volume. The cerebellum is anatomically divided into substructures that are called lobuli. Lobuli that are involved in the coordination of movements are usually more affected by volume loss than others. In the clinical routine, neurologists and radiologists screen the diagnostic magnetic resonance images (MRI) of the brain for such changes of the cerebellar volume. A quick screening, however, cannot provide exact measurements of the concrete volumes. Such a detailed manual segmentation is very time-consuming, as it requires all lobules to be delineated slice by slice on the underlying MRI. Even for a trained expert the segmentation of the cerebellum of only one patient can take a whole working day. However, volumes of cerebellar sub-structures are of special interest as they define individual parameters that can be tracked over time.
In several neurodegenerative diseases, volumetric changes are often used to evaluate the efficacy of a new medication in interventional drug trials. Using imaging markers becomes even more important for future preventive trials, in which the new medication is given to mutation carriers before the onset of ataixa. In such a scenario, clinical disease scales cannot inform about the disease severity and progression, because these individuals do not show any symptoms yet. What one do, however, is measure the cerebellar volumes and compare their evolution in patients who are receiving the verum drug in contrast to patients who are receiving the placebo. Manually quantifying cerebellar volumes in a drug study, however, is unfeasible due to the large time requirements. Segmentation algorithms that automatically parcellate the brain into its substructures are already available for the forebrain. In contrast, the availability of convenient and accurate tools for automated segmentation of the cerebellum is very limited.
In our research project, we will manually segment the cerebellum of spinocerebellar ataxia patients, specifically SCA1, 2, 3 and 6, and of healthy volunteers. These data will be used to train and evaluate an algorithm for automated parcellation built on methods from state-of-the-art computational science which includes artificial intelligence. Our research project will be realized in collaboration with the image analysis group led by Martin Reuter at the German Center for Neurodegenerative Disease (DZNE). Martin Reuter has already implemented such a fast and accurate algorithm for automated parcellation of the cerebrum. The aim of our research project is be to include also the cerebellar sub-segmentation. With this, we provide a reliable model of the distribution of volume loss in the cerebellar substructures in the most common SCAs. By developing an automated artificial intelligence tool for cerebellar segmentation, we will support researchers to easily include volumetric analysis into their work and strongly facilitate future clinical trials with new medications.
Chandrakanth Reddy Edamakanti, PhD
Northwestern University – Chicago Campus
GABAergic inhibitory interneurons as a therapeutic target for SCA1
Spinocerebellar ataxia type 1 (SCA1) is a late onset cerebellar neurodegenerative disorder caused by the mutation (abnormal polyglutamine expansion) in Ataxin-1 gene. People with this condition experience problem with coordination and balance (ataxia). The mutant protein is especially toxic to the Purkinje cells in the cerebellum that are crucial for regulating movement execution in mammals. It is very puzzling that symptoms do not appear until later in life when the mutant protein is being expressed since before birth and biological changes at the molecular level occur within the first few weeks after birth in mouse models. This is also true for many other neurodegenerative disorders. We are particularly intrigued by these early molecular changes since not only will they give insights into the early disease pathogenesis of SCA1, but we will also better understand cerebellar development. We started looking closely for changes that occur at a cellular level in cerebellum during early stages and we found the remarkable changes in function of cerebellar stem cells.
The cerebellum is a heterogeneous brain structure composed of multiple different cells with neurons and glial cells being the majority. Neurons transfer sensory information that is coming from external factors like touch, sound, or light throughout the brain and then transmit the appropriate response. Neurons are divided into two major categories, excitatory and inhibitory that stimulate or inhibit the subsequent neurons, respectively. While glial cells are known to support neuronal function, and maintain a suitable environment. Both the inhibitory neurons and glial cells in the cerebellum come from the stem cells that exist in cerebellum for first three weeks after birth. We discovered that with SCA1, the cerebellum produce high number of stem cells during development which in turn gives rise to enhanced number of inhibitory neurons (Basket cells and stellate cells) and fewer glial cells. Furthermore, the elevated number inhibitory neurons cause increased inhibition of neighboring Purkinje cells.
In this proposal, we aim to reduce the inhibition of Purkinje cells using both genetic mouse models and drug models. Both of these studies will allow us to determine whether modulating the inhibitory signals from interneurons onto Purkinje cells can improve the disease phenotype and thus can be used as a potential therapeutic target for SCA1 disease.
Rita Perfeito, PhD
Center for Neuroscience and Cell Biology (CNCB)
Intravenous delivery of the brain-targeting AAV-PHPeB encoding the cholesterol hydroxylase CYP46A1 into a mouse model of spinocerebellar ataxia type 3: a promising non-invasive therapeutic strategy
Spinocerebellar ataxia type 3 (SCA3) or Machado-Joseph disease (MJD) is the most prevalent autosomal dominant spinocerebellar ataxia in the world leading to severe clinical manifestations and premature death. MJD is a multisystem disorder with degeneration of specific brain regions that lead to a broad spectrum of clinical symptoms such as ataxia, postural instability, oculomotor impairments and neuropathy. Ataxia usually starts in midlife evolving to severe disability and death.
Cholesterol is critical for the physiology of neurons, all through development and in adult life. Deregulation of brain cholesterol and impaired brain cholesterol turnover have been linked to several other neurodegenerative disorders, including Parkinson’s disease, Alzheimer’s disease and Huntington’s disease. Excessive brain cholesterol may be deleterious to neurons, however, cholesterol does not cross the blood-brain barrier (BBB). To be excreted out of the brain and maintain its levels equilibrated, cholesterol is converted into a molecule called 24S-hydroxycholesterol (24-OHChol), which is produced by the neuronal cholesterol 24-hydroxylase (CYP46A1) enzyme. Indeed, CYP46A1 has been recognized as the key enzyme that allows efflux of brain cholesterol and activates brain cholesterol turnover and therefore, has been considered as an attractive target to treat neurodegenerative disorders.
CYP46A1 has already been shown to be decreased in the cerebellum (one of the main brain regions affected in this disorder) of SCA3 patients and SCA3 mice.
Furthermore, injection into the cerebellum of adeno-associated viral vectors (AAVs) transporting CYP46A1 in SCA3 mice models, reduced mutant ataxin-3 accumulation (a hallmark of SCA3) and protected neurons, also alleviating motor impairments associated to the disease. These viral vectors have been extensively used as vehicles for gene delivery to the nervous system (the principle of the so-called gene therapy-related approach currently and widely applied in research all over the world), however, intra-cerebellar injection is an invasive procedure, involving surgical risks and with considerable limitations from a clinical translational point of view.
Therefore, this project aims at investigating whether a non-invasive delivery of CYP46A1 will ameliorate the symptoms of the disease in a transgenic (Tg) MJD mouse model (MJD Q69 mouse) with established pathology. For this purpose, we will take advantage of an AAV vector with the capacity to overcome the blood-brain barrier and tropism for the central nervous system – the novel PHPeB-AAV variant, on whose backbone we have already inserted CYP46A1. The vectors will be injected intravenously in adult SCA3 mice and we will evaluate whether this strategy will be neuroprotective. In particular, we will investigate the levels of CYP46A1 in specific regions of the brain of these mice and analyse the reduction of mutant ataxin-3 protein aggregates, the effectiveness in alleviating motor impairments and the amelioration in the neuropathology of treated Tg mice. Furthermore, we will characterize lipidomic modifications in plasma and brain tissue of SCA3 Tg animals to corroborate the role of cholesterol metabolism impairment in SCA3 and demonstrate the efficacy of this novel strategy of gene therapy in this disorder. Finally, we will study autophagy (a “cell cleaning” pathway), as a possible mechanism underlying CYP46A1 role in SCA3.
Overall, this project will consolidate the pivotal and beneficial role of CYP46A1 and brain cholesterol metabolism in neuronal function in a SCA3 mouse model. Furthermore, the use of a non-invasive strategy of CYP46A1 delivery will bring great promises as a relevant therapeutic approach not only for Machado-Joseph disease but also for other SCAs.
Nan Zhang, PhD
Houston Methodist Research Institute
A DNAzyme that targets the CAG repeat RNA in polyglutamine diseases
The polyglutamine (polyQ) diseases are a group of neurodegenerative disorders caused by expanded CAG repeats encoding a along polyQ tract in unrelated proteins. To date, a total of nine polyQ diseases have been described, including spinocerebellar ataxia types (SCAs) 1, 2, 3, 6, 7 and 17, Huntington’s disease (HD), dentatorubral pallidoluysian atrophy (DRPLA), and the X-linked spinal and bulbar muscular atrophy (SBMA). The mutant polyQ proteins form aggregates in both nucleus and cytoplasm, leading to degeneration and vulnerability of specific neuronal subpopulations. Although animal models of polyQ diseases for studying human pathology and for assessing disease-modifying therapies are readily available, there is currently no cure or prevention of these diseases. Several therapeutic approaches are underway for animal testing and clinical trials; particularly the antisense oligonucleotide therapy against HD has reached clinical trial phase III. Data from past studies suggest that knocking down both mutant and normal polyQ proteins may not be detrimental to patients or animals and off-target effects are limited even when the CAG repeats are directly targeted. Therefore, it is possible to design a single repeat-based therapeutic entity for treatment of multiple polyQ diseases. In this proposal, we designed an RNA-cleaving DNAzyme that binds to and cleaves CAG repeats under physiological cation concentration without the requirement of protein components. We show that the DNAzyme knocks down several mutant polyQ proteins with 70-100% efficiency in cells. The highly reprogrammable nature of DNAzyme also allows targeting of unique RNA sequences, improved stability with chemical modifications and compatibility with various non-viral delivery methods.
Dr. Sharan Srinivasan, MD, PhD
Brigham and Women’s Hospital, Inc.
An isogenic iPSC model of SCA3 examining relative loss and gain of Ataxin-3 function.
As our population grows and ages, neurodegenerative diseases are increasing in frequency and the need for improved treatments is clear and dire. Unfortunately, we have struggled to develop improved therapies as our understanding of the biology of these diseases is limited by poor models and lack of resources. This chasm is especially wide in rarer neurodegenerative diseases such as ataxia. Defined as an inability to perform coordinated movements, ataxia can arise from a variety of causes, including hereditary patterns that can burden families for generations. Although less common than some other neurodegenerative diseases, these inherited ataxias can be equally debilitating. The spinocerebellar ataxias (SCAs) lead to progressive decline in speech and swallowing, limb coordination, and walking, often rendering people wheelchair-bound. While there are multiple FDA-approved medications for other neurodegenerative conditions, such as Alzheimer’s Disease, there are none available for SCA.
There are over forty subtypes of SCA, but just a few make up the large majority of patients. Of these, SCA3 is the most common worldwide, affecting about 1 to 5 in 100,000 people. SCA3 leads to ataxia, prominent difficulties with eye movements, and speech, features that can resemble another neurodegenerative state, Parkinson Disease (PD). Although both PD and SCA3 lead to loss of neurons in an identical area of the brain, the underlying cause for both diseases is incredibly different, suggesting unique pathways that converge on a common end result. However, there is significant variability in how SCA3 patients present clinically. The exact reason behind this is unclear but is thought to reflect specific changes in the gene that is affected in SCA3. Sadly, our ability to study these biological pathways is currently hampered by inadequate resources and insufficient tools.
The work proposed here focuses on developing these resources and tools. We will take advantage of novel genetic strategies that have been developed and honed over years. Our work will implement SCA3 patient-derived tissue. As physician scientists at the Brigham and Women’s Hospital specializing in movement disorders and neurodegenerative diseases, we have unique access to patients with rare diseases such as SCA3. By using skin samples easily obtained in the clinic, we can generate stem cells capable of recapitulating specific parts of the nervous system without requiring embryonic tissue or invasive procedures. By administering specific proteins, these cells can be turned into the neurons lost in SCA3 that result in parkinsonism. These stem cells will be genetically altered to recreate the disease-causing mutation of SCA3 with varying severity. Using state of the art genetic platforms, we can then analyze how these neurons are affected by the SCA3 mutation.
There is an obvious need for therapies for debilitating diseases such as SCA3. Our proposed research will generate tools we need to better understand this devastating illness and move towards targeted therapies. With these resources, we will be expertly positioned to improve patient care.
Young Investigator Awards
The Young Investigator Award was created to encourage young clinical and scientific investigators to pursue a career in the field of Ataxia research. It is our hope that Ataxia research will be invigorated by the work of young, talented individuals supported by this award.
Collin Anderson, PhD
University of Utah
Gene therapy in the Shaker rat model of cerebellar degeneration and ataxia
Our work revolves around the generation of a novel gene therapy to treat a form of degenerative cerebellar ataxia. We have spent several years characterizing the cellular, molecular, and motor abnormalities of the shaker rat, a naturally occurring genetic rodent model of Purkinje cell degeneration, cerebellar tremor, and ataxia. In studying the shaker rat, we identified the causative mutation: shaker rats lack a functional NHE6 ion channel, which functions by removing hydrogen ions from Purkinje cells and replaces them with sodium ions. In the absence of this channel, cells become overly acidic and eventually die, leading to severe ataxia and tremor. Mutations of the gene encoding this ion channel lead to Christianson Syndrome in humans, which includes a severe, debilitating, progressive ataxia. We are working to characterize and optimize the effects of a new therapeutic strategy in this model: we have designed an adeno-associated virus that expresses the unmutated gene in Purkinje cells, generating a functional NHE6 protein. Adeno-associated viruses are a particularly attractive method of gene therapy in humans, as they don’t cause disease in humans, don’t replicate, and have long-lasting effects. Additionally, we have designed this virus using the newest engineered variant, enabling not only high efficacy with low dose, but ability to cross the blood-brain barrier. Therefore, success in our work will lead to easier translation than that in most therapeutic strategies. We have already generated very strong preliminary data showing that, at least over a moderate term, this viral therapeutic can prevent the generation of phenotype, but we still need to determine whether whether we are preventing the phenotype or simply delaying it. We need to perform experiments to optimize the therapy, and, further, while AAVs are known to be safely tolerated, we need to evalute the safety profile of the gene expression. Not only will this work develop a translatable therapy for ataxia associated with Christianson Syndrome, but it will prove the concept of using gene therapies to restore missing protein expression in order to treat a degenerative ataxia, which has major implications for the way we treat ataxias.
Angela Mabb, PhD
Georgia State University
Resolving sex differences in the onset of motor dysfunction in Gordon Holmes syndrome
Neurons are a type of cell in the brain that communicate electrical and chemical signals. However, there are other cell types in the brain that support neuron communication activities. There is increasing evidence that indicates that alteration of these non-neuron cell types may accelerate or cause neurological disease if altered. Gordon Holmes syndrome (GHS) is a neurological disease that is caused by deletion of the RNF216/TRIAD3 gene in all cell types. Individuals with GHS have reproductive failure, slurred or slow speech, dementia, a lack of motor coordination (ataxia), and a drastically reduced lifespan. There are currently no effective treatments for GHS. Although limited in scope, clinical evidence suggests that GHS affects males and females differently. Due to the rarity of the disease, (prevalence in the human population is 1 in 100,000) it is difficult to study. In an attempt to predict the progression of GHS in males and females, we generated a GHS mouse model in which the Rnf216/Triad3 gene was deleted. We found that males and females without this gene develop different patterns of motor impairments. Surprisingly, removal of Rnf216/Triad3 specifically in a class of non-neuron cell types called astrocytes, resulted in similar motor impairments in males and females. Our research suggests that a lack of RNF216/TRIAD3 specifically in astrocytes may be causing motor impairments in GHS. The goal of this proposal is to further explore how motor impairments progress throughout the lifetime of males and females in Rnf216/Triad3 global and Rnf216/Triad3 astrocyte-specific knockout mice. These experiments will allow us to understand how impairments in motor coordination differ between males and females and will determine how non-neuron cell types in the brain are involved. Given the low frequency of GHS patient accessibility and late-stage GHS diagnosis, our results could serve as a predictive measure for the clinical onset of ataxia between male and female GHS individuals, and resolve sex-differences in the development of motor dysfunction in GHS. Our work could also provide insight into the emergence of sex differences in other forms of ataxia disorders, such as autosomal dominant inherited forms of spinocerebellar ataxia (SCAs).
Elena Restelli, PhD
Pharmacological Research Institute Mario Negri
A gene therapy approach for Marinesco-Sjögren syndrome
Marinesco-Sjogren syndrome (MSS) is a very rare, early-onset, autosomal recessive disease characterized by difficulties in motor coordination and speech, muscle weakness, which impairs autonomous standing and walking, and frequent congenital bilateral cataracts. These symptoms become more severe with time, then stabilise allowing an almost normal life-span. To date, MSS is not treatable and patient care is limited to rehabilitative cures. Recently, the SIL1 gene was identified as responsible for the majority of MSS cases. SIL1 mutations lead to death of several cell types, cerebellar neurons and muscle cells, causing the main symptoms of the disease. The aim of this project is to test whether the introduction of functional Sil1 gene by a gene therapy approach prevents motor deficits and cerebellar and muscle degeneration in a mouse model of MSS. Results of this project are expected to provide proof-of-principle that gene therapy is a viable therapeutic strategy for MSS, and may lay the ground for testing gene therapy in carriers of the SIL1 mutation.
Post Doc Fellowship
Post-Doctoral Fellowship Awards are to serve as a bridge from post-doctoral positions to junior faculty positions. Recipients have shown a commitment to research in the field of Ataxia.
Dr Raphael Benhamou, PhD
The Scripps Research Institute – Florida
Small molecule targeting of CAG repeats in Ataxias
The Spinocerebellar ataxias (SCAs) are a class of degenerative diseases characterized by changes in the part of the brain related to the movement control (cerebellum) and in the spinal cord. There are many different types of SCA, and they are classified according to the mutated (altered) gene. SCA subtypes 1, 2, 3, 6 and 7 are cause by a triplet repeat expansion of (CAG) RNA that leads to the formation of an abnormally long protein that then forms toxic aggregates. To date, there are no disease-modifying therapies for SCAs caused by repeat expansions . Since the aggregated proteins implicated in these diseases act through a dominant gain-of-function mechanism resulting in neurotoxicity, suppression of the mutant protein is an appealing and promising approach to slow or halt disease progression. Therefore one promising therapy is to prevent the toxic proteins from being synthesized by targeting the RNAs that encode them.
Indeed, our proposed work focuses on inactivating and/or eliminating SCA RNAs with drug-like small molecules that bind and cleave the RNA repeat expansion. These groundbreaking approaches have the potential to establish a completely new paradigm for small molecules that target toxic structured RNAs implicated in SCA diseases.
Dr. Hannah Shorrock, PhD
Research Foundation of SUNY – University at Albany
A CAG expansion-selective small molecule screen for multiple spinocerebellar ataxias
The spinocerebellar ataxias (SCAs) are a group of dominantly inherited neurodegenerative diseases. While SCAs can be caused by a variety of genetic mutations, a large sub-group are caused by CAG repeat expansion mutations in different genes. These CAG expansion SCAs include SCA types 1, 2, 3, 6, 7 and 12, all of which involve expression of expansion RNAs and some the expression of toxic polyglutamine proteins. There are currently no approved treatments for these diseases and preclinical therapy development mainly focuses on disease-specific approaches. The goal of my proposal is to screen and identify compounds that provide therapeutic efficacy across the family of SCAs caused by CAG repeat expansions. To accomplish this goal, I will generate a cell line that express both a tagged (CAG)60 repeat expansion and a no-repeat control transcript and screen small molecule libraries in this cell line to identify compounds that selectively reduce levels of the toxic (CAG)60 expansion transcripts. As the (CAG)60 expansion will not be in the genetic context of any specific SCA, this screen is designed to identify compounds that selectively target expanded CAG transcripts independent of the gene-specific sequences. Therefore, compounds that I identify are likely to have therapeutic potential against multiple SCAs. These candidate compounds along with selected compounds which show efficacy in other repeat expansion disorders will then be used to treat patient-derived cell lines from multiple SCAs to compare therapeutic efficacy and mechanism of action. I will assess the effect of treatment on the expression of CAG expansion RNAs, polyglutamine expansion proteins and downstream phenotypes specific to each SCA. This approach provides an exciting opportunity to not only understand common SCA pathogenic mechanisms but also to develop novel candidates that have therapeutic potential across multiple SCAs.
Yijing Zhou, PhD
The Children’s Hospital of Philadelphia
Uncovering the pathogenic mechanisms of cerebellar atrophy with SNX14 deficiency
Cerebellar ataxia is a heterogeneous group of disorders characterized by imbalanced movements and poor motor coordination. These are usually due to impaired function or damage in the cerebellum. The disease is often genetically inherited and affects ~9 per 100,000 individuals. Although more than 100 genes have been implicated to be associated with the disease, how they cause cerebellar ataxia is still largely unknown. As a result, so far, there is no specific treatment for ataxia. This situation highlights the need for further studies to provide a more comprehensive understanding of the disease mechanisms, from where scientists may find drug targets and develop specific treatments for cerebellar ataxia.
Spinocerebellar ataxia autosomal recessive 20 (SCAR20) is a particular form of cerebellar ataxia. The patients are usually diagnosed early after birth. They usually show a progressive shrinking of cerebella, intellectual disability, and dysmorphic facies. Our recent work identified that mutations in the gene Sorting Nexin 14 (SNX14) are the causes of SCAR20. SNX14 is involved in regulating the function of lysosomes, which are the cellular compartments responsible for the degradation of waste materials inside of cells. Lysosome dysfunction has previously been associated with cerebellar degenerative diseases. However, it is not well understood how lysosome dysfunction leads to cerebellar damage.
In order to uncover how SNX14 mutations lead to lysosome dysfunction and SCAR20, we have generated a mouse model that shows impaired movement reminiscent of patients with cerebellar ataxia. Our current work aims to characterize the type of cerebellar damage present in these mice. Specifically, we will check if the shapes or functions of the lysosomes are changed in their cerebella. Future work will be focused on seeking for cellular materials that may toxically accumulate in SCAR20 cerebella due to lysosome dysfunction. Our ultimate goal is to find methods to prevent cerebellar damage.
With this study, we expect to uncover the disease mechanisms of SCAR20. Moreover, our research will help doctors and scientists better understand the importance of lysosomes in the cerebellum. We may reveal targets for the development of drugs, not even for SCAR20, but also for a broader spectrum of spinocerebellar ataxia.
Tiffany Thibaudeau, PhD
Northwestern University – Evanston Campus
Unraveling the mechanisms of impaired protein degradation systems in spinocerebellar ataxia type 3
Spinocerebellar ataxia type 3 (SCA3), also known as Machado-Joseph disease (MJD) is the most common form of spinocerebellar ataxia in the world. The main clinical hallmark of SCA3 is a dysfunction of motor coordination that can affect gaze, speech, gait and balance. SCA3 is caused by an abnormal expansion in the axtaxin-3 protein, called a polyglutamine (polyQ) repeat, which causes the ataix-3 protein to clump together into aggregates. Ataxin-3 is expressed in most human tissues and has a role in maintaining protein homeostasis (proteostasis). If protein homeostasis declines, misfolded proteins begin to accumulate and aggregate in the cell, which can disrupt normal cellular functions and even cause cell death. Protein degradation is a key mechanism to avoid accumulation of misfolded and damaged proteins. The two main protein degradation systems in the cell are the ubiquitin-proteasome system (UPS) and autophagy-lysosome pathways. Evidence suggests axatin-3 aggregates impair both protein degradation systems which contributes to disease pathology. However, researchers do not yet know exactly why the protein degradation systems fail and how the body responds across tissues to compensate for this failure. Understanding the interplay of proteasome activity and autophagy in SCA3 (and other polyQ disorders) could identify novel targets for therapeutic intervention.
Oleg Chertkov, PhD
Instituto de Biologia Molecular e Celular – IBMC
Protein-protein interaction of Ataxin3
Age-related neurodegenerative disease as one of the leading medical and societal challenges faced by EU and Global society. Existing treatments for neurodegenerative diseases are very limited, and only treat the symptoms, rather than addressing the cause, because we still don’t fully understand the causes and underlying biology of these diseases. This very relevant project could help reveals biological basis group of polyQ diseases and develop approaches for their treatment.
Spinocerebellar ataxia type-3 (SCA3), also known as Machado-Joseph disease (MJD), is a neurodegenerative disorder caused by the expansion of a CAG trinucleotide repeat, codifying for amino acid glutamine, in the gene associated to the disease – Ataxin-3 (ATX3) – leading to the expansion of the polyglutamine (polyQ) tract within the translated protein. This mutation increases Atx3 propensity to aggregate leading to its accumulation as intracellular inclusions in specific neuronal cells leading to neurodegeneration and ultimately to the patient’s death.
A critical and still unanswered question is why the expanded protein selectively damages a particular subset of neurons leading to the specific symptoms that affect patients with ataxia. In particular, several studies show that the cell nucleus is central for ataxin-3 neurotoxicity. In this protect we will explore the hypothesis that differences in protein-protein interactions in the expanded and non-pathogenic ataxin-3 are key for the pathogenesis mechanisms. Therefore, we will study the biochemical and structural features of these interactions, that will provide the starting point for screening small molecules able to finely modulate those interactions and decrease neurotoxicity. Thereby, perspective candidates developed in this project could be use as drug in MJD therapies.
Despite the extensive research in the field, no effective MJD therapies have been developed so far and the treatment is merely symptomatic. The proposed strategy will be critical to improve our understanding of MJD pathogenesis and to develop effective drugs for targeted therapies to fight this extremely incapacitating disease, improving patient’s quality of life and healthspan.