The Laboratories….. Researchers working on Myotonic Dystrophy

Here are a few of the labs working on Myotonic Dystrophy

Dr. Puymirat Quebec, Canada
The major aim of the Puymirat lab is to develop a genetic therapy for Steinert dystrophy. During the last few years, the Puymirat lab developed a genetic approach capable of restoring normal functions of the affected human muscle cell. Indeed, Steinert dystrophy is caused by an abnormal accumulation of RNA in the nucleus of muscle cells. The therapy developed by the Puymirat lab is based on the specific destruction of RNA using antisense RNA and ribozymes. The research group showed in vitro that specific destruction of mRNA restored normal functions of the cell. In vivo, intramuscular injection of vectors producing antisense RNA or ribozymes reduced the levels of mutated RNA by 80%. The team is currently studying the effectiveness of this therapy in mice carrying the pathology.

             The Puymirat laboratory is also interested in the study of mechanisms responsible for this pathology, particularly on the identification of abnormally produced proteins. Dr Puymirat’s research group is also studying mechanisms responsible for congenital forms of the disease. 

              In addition, Dr Puymirat’s team is interested in developing tools in order to quantify the deficit caused by this pathology and on the use of muscle imagery (MRI and PET scan) to quantify muscle functions. Researchers of the Puymirat lab also conduct clinical trials aimed at reducing the symptoms of the disease. Finally, Dr Jack Puymirat is responsible for the Provincial Network of Neurogenetics and for the clinical diagnosis laboratory.

Human genetic department

2705,  Laurier Boulevard. RC-9300. Quebec (Quebec) Canada. G1V 4G2. Phone: +1 (418) 654-2186. Fax: +1 (418) 654-2207.

E-mail: sec.genetique@crchul.ulaval.ca

 

Senator Paul Wellstone Muscular Dystrophy Research Center
Centers of Excellence

The National Institutes of Health (NIH) established centers of excellence for muscular dystrophy research through Congressional Acts passed in the years 2001 and 2008. The NIH currently funds six Senator Paul D. Wellstone Muscular Dystrophy Cooperative Research Centers (MDCRCs). The University of Rochester Medical Center (URMC) was one of the three centers nationwide designated as a MDCRC from 2003-2008. We have received additional support from 2008-2013.

The goals of MDCRCs are to establish research programs focused on major questions about muscular dystrophy. MDCRCs are designed to centralize the expertise, infrastructure and resources needed to conduct innovative, cross-disciplinary and multi-institutional research programs with state-of-the-art technologies. They serve to expand the resources available to investigators and to physicians diagnosing and treating people with muscle diseases and contribute to the training of new researchers for the muscular dystrophy field.

MDCRCs promote parallel research in three main areas:

  • Basic research or studies that explore the cellular or “mechanisms’ of how muscular dystrophies develop and progress. For example, studies in the laboratory to measure muscle cells or to screen new drugs.
  • Translational research to study how discoveries or drugs tested in laboratory test tubes and other research models “translate” or compare to the effects of these drugs in human studies.
  • Clinical research to study drugs, devices, or other treatments in human subjects and to determine if these therapies are safe and beneficial to patients.

Strengths of the University of Rochester Medical Center MDCRC

  • Comprised of world-renowned investigators and research professionals in the URMC Department of Neurology
  • Linked to the NIH supported Clinical and Translational Science Institute at URMC – one of the first nationwide centers of excellence in translational research, designed to bring new preventive interventions, diagnostic procedures and treatments to patients and communities faster than ever before;
  • Dedicated and well-characterized patients with myotonic dystrophy (DM) and patients with facioscapulohumeral muscular dystrophy (FSHD) who are eager to support research and to participate in clinical studies through a NIH sponsored National Registry.

Director

Richard T. Moxley III, MD

Co-director

Charles A. Thornton, MD

Executive Committee

Richard T. Moxley III, MD
Charles A. Thornton, MD
Maurice Swanson, PhD
Rabi Tawil, MD
Hugh Higgins

Contact Information

Tracy Forrester
University of Rochester Medical Center
601 Elmwood Ave, Box 673
Rochester, NY 14642
Phone: 585-275-7434
Email: tracy_forrester@urmc.rochester.edu

Last updated 5/18/2009

Tom Cooper Laboratory

The recent realization that most human genes generate multiple protein isoforms via alternative splicing has revealed an extensive degree of regulation that remains to be explored.

The Tom Cooper Lab is interested in understanding the mechanisms of this regulation, from how RNA binding proteins regulate splicing of individual pre-mRNAs to the signaling events that coordinate splicing networks during development.

We also study myotonic dystrophy, the most common form of adult onset muscular dystrophy, in which disrupted splicing regulation causes the primary features of the disease.

Tom Cooper, M.D.
S. Donald Greenberg Professor of Pathology
Office Phone: 713-798-3141
Lab Phone: 713-798-5021
Fax: 713-798-5838

 Andy Berglund Laboratory

Andy Berglund
Andy Berglund
Associate Professor of Chemistry
B.A., University of Colorado
Ph.D., Brandeis University
Member of: Institute of Molecular Biology
Office: Willamette Hall Room 334
Telephone: 541-346-5097
Lab: Willamette Hall Rooms 309 & 310
Telephone: 541-346-1576 or 541-346-1594

Website
Email

Research Interests

The primary goal of the Berglund lab is to understand how introns are recognized in the process of pre-mRNA splicing. Pre-mRNA splicing is conserved from yeast to humans and a complex molecular machine, the spliceosome, is responsible for removing introns from pre-mRNAs. The factors (U1 snRNP – an RNA-protein particle, U2AF65, U2AF35 and BBP/SF1) shown in the figure are the primary factors responsible for initial intron recognition. We are using both biochemical and biophysical techniques to study these RNA-RNA, RNA-protein and protein-protein interactions. These interactions are critical because without the correct choice of splice sites, truncated proteins or proteins with the wrong sequence would be produced. Incorrect splice site selection is thought to be responsible for 15% or more of human diseases.

We are characterizing these RNA-RNA and RNA-protein interactions from multiple organisms. These include the yeast Saccharomyces cerevisiae which is an excellent model system because the introns are small and apparently there is very little or no regulation of splicing. However, in humans, the regulation of pre-mRNA splicing is very important. Almost all genes in humans contain introns and many of these genes are regulated at the level of pre-mRNA splicing. This regulation frequently results in alternative splicing which suggests that although there are only approximately 25,000 genes in the human genome the number of proteins produced is much higher than this. The control of this regulation occurs through RNA sequences found in either the intron or exon acting as either repressor or enhancer elements to influence the percentage of intron removal, splice site selection, or exon skipping. The interplay of the factors that bind these enhancer/repressor elements and their interactions with the general splicing factors (U2AF65/35, BBP/SF1 and U1 snRNP, see figure) is another focus within the lab.
Myotonic Dystrophy

The splicing factor, muscleblind (MBNL), regulates alternative splicing by affecting splice site selection (figure). Myotonic dystrophy (a form of muscular dystrophy) occurs when MBNL does not properly function. The dysfunction of MBNL occurs in a novel manner in the disease state MBNL is mis-localized and cannot act on its target pre-mRNAs. MBNL is mis-localized by binding to CUG triplet expansion repeats in the 3′ UTR of the dystrophia myotonia protein kinase (DMPK) gene. Hundreds of CUG repeats are common in patients with myotonic dystrophy while unaffected individuals have 5-30 CUG repeats. Longer CUG repeats (1,000 or more) results in more MBNL protein being mis-localized and leads to a more serious form of myotonic dystrophy because the regulation of alternative splicing of various pre-mRNAs is more severely compromised due to the increasing amounts of mis-localized MBNL. Using biochemical and biophysical methods we are studying the interaction between MBNL and the triplet expansion CUG repeats as well as MBNL’s interactions with its normal pre-mRNA targets to gain insight into the molecular mechanisms of myotonic dystrophy and alternative splicing.

Intron Recognition and Regulation of Splicing

Ralf Krahe, Ph.D. Laboratory

Present Title & Affiliation

Primary Appointment

Professor, Department of Genetics, University of Texas MD Anderson Cancer Center, Houston, TX

Dual/Joint/Adjunct Appointment

Professor, University of Texas Graduate School of Biomedical Sciences, Houston, TX

Research Interests

  • Research Interests
  • Human and molecular genetics
  • Cancer genetics
  • Neurogenetics
  • Genomics

Research in the Krahe laboratory focuses on the identification and characterization of human disease genes and their mutations/variants, including inherited cancer syndromes (Li-Fraumeni Syndrome) and the myotonic dystrophies (DM), by classic and molecular genetics and genomics approaches.

Li-Fraumeni syndrome (LFS) is a genetically heterogeneous, rare inherited cancer syndrome. Most cases are due to mutations in the tumor suppressor p53. We have mapped a novel LFS predisposition locus to 1q23, the gene for which we are identifying. In p53 and non-p53 LFS, there is evidence for risk modifiers and factors inaddition to the inherited susceptibility. We are using integrated approaches combining genomic and epigenomic profiling to dissect the complex genetic and epigenetic events underlying LFS tumorigenesis. To dissect the pathophysiological consequences of variant genes, we are generating suitable LFS mouse models. LFS predisposition and/or modifier genes may also be functionally important in other tumor types lacking a clear genetic predisposition. The molecular characterization and classification of sporadic cancers (head and neck and lung cancer, and gliomas) through genomics methodologies to identify genomic, epigenomic and transcriptomic changes underlying tumor initiation, progression and metastasis is another focus.

Myotonic dystrophy, themost common adult neuromuscular disorder, is caused by mutant (CTG)DM1 or (CCTG)DM2 expansions that when transcribed cause disease. It is unclear how these mutant (CUG)DM1/(CCUG)DM2 RNAs mediate their disease-causing effects at the molecular and cellular level. To dissect the pathophysiology, we are using functional genomics and molecular genetics approaches and have generated transgenic, knock-in and knock-out mouse models.

View a complete listof publications.

Office Address

The University of Texas MD Anderson Cancer Center
Department of Genetics, Unit 1010
1515 Holcombe Blvd.
Houston, TX 77030
Room Number: S13.8316B
Phone: (713) 834-6345
Email: rkrahe@mdanderson.org

Mani S. Mahadevan, M.D. Laboratory

Mani S. Mahadevan, M.D. Faculty Profile

MahadevanMani

Mani S. Mahadevan, M.D.

Professor of Pathology

Medical Director of Molecular Diagnostics Laboratory

EDUCATION:

Medical School: University of Ottawa, Ottawa, Canada. 1986
Internship: Victoria Hospital, London, Ontario, Canada. 1986-1987
Residency: University of Ottawa, Ottawa, Canada. 1987-1991
Research Fellowship: Children’s Hospital of Eastern Ontario (CHEO), Ottawa, Canada. 1991-1995

RESEARCH:

Our research is in the field of human genetics.  Specifically, we are studying the molecular genetics and biology of myotonic dystrophy (DM), the most common inherited neuromuscular disorder in adults.  We have previously cloned the gene for DM and identified the DM mutation as a CTG trinucleotide repeat expansion in the 3’ untranslated region of a gene encoding a serine-threonine protein kinase (DMPK).  The DM mutation was one of the first members of growing family of triplet repeat mutations causing human disease.  However, the mechanism by which it causes disease is unknown.  We are studying the effects of the DM mutation on gene expression and RNA metabolism.  These studies involve the establishment of cell culture and transgenic mouse models of disease pathogenesis, the identification and characterization of RNA-binding proteins interacting with the DMPK transcript, and studying the role of the mutant DMPK 3’UTR mRNA in inhibiting normal muscle development.  Our data shows that the mutant DMPK 3’UTR mRNA is trapped as distinct foci in the nucleus, and that its expression is sufficient to inhibit normal muscle differentiation. Our long-term goals are to understand the molecular mechanisms underlying DM and the establishment of model systems with which new approaches to therapeutic intervention could be developed and studied.  Furthermore, the study of the DM mutation has led to an active research program in RNA processing, RNA transport and muscle development.

The Wolfson Centre for Inherited Neuromuscular Disease

Group picture!

  • The Wolfson Centre is committed to finding new treatments for inherited neuromuscular disease by bringing together three disciplines under one roof in the new, purpose-built TORCH Building

     

    Clinical Research (Head: Dr. Ros Quinlivan)

    Muscle Pathology Research (Head: Prof. Caroline Sewry)

    Laboratory Research (Head: Prof. Glenn Morris)

    The Neuromuscular Research Laboratory

    PRINCIPAL RESEARCH AREAS

    • Production and epitope mapping of monoclonal antibodies and their applications.
    • Molecular pathogenesis and diagnosis of human diseases, especially inherited neuromuscular diseases.
    • Mass spectrometry and proteomics.
  • Monoclonal Antibody Database
  • Research Objectives
  • Training (Ph.D. and Masters).
  • Current Projects
  • Publications
  • Services
  • Personnel
  • Contact
  • Article in “Target MD”
  • Group photo 1998
  • See our work on the front cover of Trends in Molecular Medicine.
  • Richard Wilson – Welsh Painter, 1713-1782.
  • Alyn Valley Woods Website (Nature Conservation).

  • RESEARCH OBJECTIVES

    Our aim is to produce monoclonal antibodies as highly-specific research tools for analysis of molecular mechanisms in the pathogenesis of human genetic disease and for improved diagnosis. This involves producing large numbers of antibodies and identifying their binding sites on the protein antigen by a variety of epitope mapping techniques. The Group has an extensive network of clinical and scientific collaborators in hospitals, universities and research institutes in the USA, Canada, Japan, New Zealand, VietNam, Israel, Europe and the UK. We have a special interest in neuromuscular disease. Current research grant funding is provided by the Jennifer Trust, the American Muscular Dystrophy Association, AFM (Association Francaise contre les Myopathies) and the NINDS-NIH “SMA Project“. We also have a long association with medical centres in VietNam, offering help with training and with development of modern diagnostic methods for muscular dystrophy, hepatitis, malaria and dengue fever; this work is supported by Medical and Scientific Aid to VietNam, Laos and Cambodia.

    TRAINING

    We accept students for both M. Phil. and Ph. D courses (University of Keele; examination by thesis), part-time and full-time, if appropriately qualified (B. S. Class II div 1 or higher for Ph. D.) and funded. The group currently has two full-time students.

    CURRENT PROJECTS

    • Monoclonal antibody studies of myotonic dystrophy (muscleblind [MBNL] and msh3).
    • Monoclonal antibody studies of nesprins in Emery-Dreifuss MD.
    • Proteomic studies of spinal muscular atrophy.
    • Cellular models for McArdle Disease
    • An SMN ELISA to find new drugs for spinal muscular atrophy
    • Monoclonal antibody studies of dystrophin and related proteins.

    PAST PROJECTS

    • Monoclonal antibody studies of myotonic dystrophy (muscleblind, DMPK and Six5). [publication]
    • Monoclonal antibody studies of huntingtin. [publication]
    • Monoclonal antibody studies of emerin and lamin A/C in Emery-Dreifuss MD. [publications]
    • Monoclonal antibody studies of SMN and NAIP in spinal muscular atrophy. [publication]
    • Monoclonal antibody studies of schizophrenia (dopamine receptors).
    • Phage display technology and epitope mapping. [publications]
    • Immune response to hepatitis C infection. [publication]
    • Creatine kinase and protein folding. [publication]
    • Detection of allergens in food.

    PUBLICATIONS

    SERVICES

    Specialized equipment available includes a cell culture suite, a fluorescence photomicroscope with image analysis, a BioRad Radiance 2000 confocal microscope, a Leica SP5 confocal microscope, a BIAcore-X biosensor for biomolecular interaction analysis, ABI nanospray QTrap 3200 and MALDI 4800 Mass Spectrometers and a range of preparative ultracentrifuges.

    CONTACT

    Professor G. E. Morris,
    Wolfson Centre for Inherited Neuromuscular Disease,
    TORCH Building,
    RJAH Orthopaedic Hospital,
    OSWESTRY,SY10 7AG
    U.K.Tel. 01691 404155 (+44 1691 404155)
    Fax 01691 404170 (+44 1691 404170)
    Email: glennmanc@hotmail.com

Laura Ranum, Ph.D. Laboratory

Laura Ranum

Professor, Department of Molecular Genetics and Microbiology of the University of Florida College of Medicine.

Professor, Ph.D. University of Minnesota, 1989

Areas of Research Strength:

Neuroscience Human genetics Muscular Dystrophy Ataxia

Research Techniques Used:

Human genetics, genetic mapping, positional cloning, transgenic models

Research Interests:

Many neurodegenerative diseases begin later in life after the nervous system is fully developed. A major step towards a better understanding of neurodegenerative diseases was made with the discovery that microsatellite repeat expansions are responsible for a large group (>30) of these diseases. In these disorders, extra copies of short DNA repeats (e.g. CTG•CAG or CCTG•CAGG) cause disease. In general, these mutations are thought to cause disease by protein loss-of-function, protein gain-of-function or by RNA gain of function mechanisms. My group uses human genetics to define the molecular causes of neurological disorders and mouse models to understand how these mutations cause neurons in the brain to die.

RNA gain-of-function SCA8 and DM: In 1999 we discovered that a novel form of ataxia, spinocerebellar ataxia type 8 (SCA8), is caused by a CTG•CAG expansion mutation (Nature Genetics 21:379-384). In 2001 we showed that a second form of myotonic dystrophy (DM2) is caused by an intronic CCTG•CAGG tetranucleotide expansion (Science 293:864-867). These discoveries and additional work by others have established that CUG/CCUG expansion RNAs dysregulate alternative splicing pathways. To understand the impact of these expansion mutations on the central nervous system (CNS) we developed SCA8 and DM mouse models (Nature Genetics 38:758-769, 2006; and Margolis et al., in preparation). Our SCA8 mice showed, for the first time, that CUG expansion transcripts cause RNA gain-of-function effects in the brain and that relatively short expansions (~100 repeats) are sufficient in length to effect these changes (Plos Genetics 5:e1000600, 2009). We are currently characterizing our DM and SCA8 mice using a combination of molecular and in vivo optical-imaging strategies to determine if specific alternative splicing changes caused by CUG and CCUG expansion transcripts lead to neuronal phenotypes.

Bidirectional expression of CAG•CTG expansion mutations: Our work also led to the novel discovery that the SCA8 expansion mutation is bi-directionally transcribed and expresses expansion transcripts in both the CUG (ataxin 8 opposite strand, ATXN8-OS) and CAG (ataxin 8, ATXN8) expansion transcripts (Nature Genetics 38:758-769, 2006). The ATXN8 transcripts express a nearly pure polyglutamine expansion protein from an ATG-initiated open reading frame (ORF). This was the first demonstration that a microsatellite expansion mutation could be expressed in both directions. Since this report, bidirectional expression has been shown to also occur for many other triplet expansion disorders including DM1, FXTAS, SCA7, HD and HDL2. These results raise the possibility that RNA gain-of-function effects contribute to diseases currently thought to be caused by protein gain-of-function effects and that unrecognized expansion proteins play a role in disorders known to involve RNA gain of function mechanisms. We are currently exploring the potential pathogenic role that bidirectional transcription plays in SCA8 and other microsatellite expansion disorders.

Repeat Associated Non-AUG Translation (RAN-Translation): A major surprise that has recently come out of our work is that the canonical rules of translational initiation do not apply for CAG and CUG expansions and that these repeats express homopolymeric proteins in all three frames without an ATG-initiation codon. We showed this repeat associated non-AUG translation (RAN-translation) depends on RNA structure and repeat length and that RAN-translation occurs in vivo in DM1 and SCA8 (PNAS 108:260-265, 2011). We are now addressing a number of provocative questions that this discovery raises including: 1) How does this novel translational initiation mechanism work? 2) Is RAN-translation a key, previously unrecognized, pathogenic mechanism in neurological disease? 3) Are other repetitive sequences in the genome translated into proteins and if so, what is their function?

Spectrin mutations in SCA5. My lab is also involved in the discovery and characterization of other types of novel gene mutations. In 2006 we showed spinocerebellar ataxia type 5 (SCA5), is caused by mutations in the spectrin beta non-erythrocytic 2 (SPTBN2) gene (Nature Genetics 38:184-90, 2006) which encodes the β-III spectrin protein. We recently developed novel mouse and fly models of SCA5 to better understand how SBTBN2 mutations affect protein function and to model the human disease. Additional studies focus on understanding how mutations in SPTBN2 alter cellular function and cause disease.

Novel Human Gene Discovery. Additionally, my laboratory continues to search for novel human disease genes. We are using high-throughput sequencing strategies to look for single-gene mutations that cause novel forms of ataxia, amyotrophic lateral sclerosis (ALS) and neuropsychiatric diseases.

Sita Reddy Laboratory

Associate Professor

Biochemistry & Molecular Biology
Keck School of Medicine
Institute for Genetic Medicine

Research Topics

  • Developmental Biology
  • Cardiovascular & Skeletal Muscle Diseases
  • DNA Replication, Repair, Modification, Neurogenetics

Research Overview

My laboratory is interested in the molecular defects that contribute to the development of myotonic dystrophy. The myotonic dystrophies, DM1 and DM2, are multi-symptom disorders characterized by a wide range of muscle and neurological defects. We are using both mouse genetics and biochemical approaches to understand the molecular basis of these diseases.

The genetic defects in DM1 and DM2 are expansions of CTG and CCTG repeat tracts located in untranslated regions of two genes, DMPK and ZNF9, located on chromosome 19q and 3q, respectively. DM1 is the more serious disorder, exhibiting both unique features and demonstrating increased incidence and severity of several symptoms shared between the two disorders. We are currently testing the following hypotheses:

(i) Unique features of DM1 arise from locus specific cis effects of CTG expansion

(ii) A dominant RNA mechanism underlies shared features of both diseases

(iii) Disruption of aberrant interactions between the muscleblind proteins and the mutant RNAs is sufficient to rescue pathological features that are common to both diseases.

Cis effects of CTG expansion in DM1: CTG expansions in DM1 patients have thus far been shown to cause stochastic decreases in the steady-state levels of two genes, DMPK and SIX5, which are located in the vicinity of the CTG tract. We are testing the hypothesis that locus specific cis effects of CTG expansion contribute to the increased severity and complexity of the symptoms exhibited by DM1 patients. This hypothesis predicts that inactivation of DMPK and SIX5 should result in partial DM1 phenotypes in model animals. To test this model, we have developed mice in which Dmpk and Six5 have been functionally inactivated. Analyses of these mouse strains demonstrate that decreased levels of Dmpk and Six5 result in a unique set of pathophysiological features that are observed in DM1 patients. Specifically, reduced Dmpk levels results in skeletal muscle weakness, ion channel defects and cardiac conduction disease while Six5 loss increases the incidence of congenital cataracts, cardiac hypertrophy and gonadal dysfunction. Defining the number of genes affected at the DM1 locus and understanding their contribution to the DM1 phenotype are current interests of the lab. These analyses will be carried out using a mouse model of DM1, in which expanded CTG tracts have been introduced into the corresponding mouse Dm1 locus.

RNA dominant mechanism: An RNA dominant mechanism has been shown to underlie the development of several pathological features that are common to both DM1 and DM2. Specifically, mutant RNAs encoding expanded CUG and CCUG repeat sequences are known to sequester the muscleblind family of proteins to form aberrant nuclear foci. We have shown that the muscleblind proteins are RNA splice regulators and that dysregulation of their activity results in RNA splice defects in DM patient cells. In ongoing experiments we are assessing the role of the muscleblind family of genes in DM by developing single and double mutants of the muscleblind family of genes in mice. In a parallel series of experiments we are attempting to understand the molecular basis of the toxicity associated with expanded CUG/CCUG tracts by functional characterization of the protein profile of DM nuclear foci using molecular and biochemical approaches.

Screening chemical libraries for small molecules that rescue DM pathology: We are currently developing molecular screens to identify small molecules that disaggregate DM foci in patient cells and allow a rescue of the DM associated splice defects. The effectiveness of such molecules in rescuing features of DM pathology will be further assessed in vivo using mouse models for DM that are under construction in my lab.

David Brook

Professor of Human Genetics, Faculty of Medicine & Health Sciences

Contact

Biography

University of Manchester BSc 1979, University of Edinburgh PhD 1983, University of Wales College of Medicine Post-Doc 1982 – 1989, Massachusetts Institute of Technology Post-Doc 1989 – 1992, University of Nottingham Senior Lecturer 1992 – 1995, Professor 1995 – present, Head of the Institute of Genetics 2000 – 2003, Head of the School of Biology 2003 – 2008.

Teaching Summary

Human Molecular Genetics

Research Summary

Molecular genetic studies to identify genes involved in cardiac development: Holt-Oram syndrome (HOS) is an inherited disorder that affects the development of the heart and upper limb. Whilst HOS is… read more

Understanding the molecular basis of myotonic dystrophy

Myotonic dystrophy (DM) is the most common form of muscular dystrophy affecting adults. DM is caused by the expansion of a repeated DNA sequence, CTG, which is located in the 3? untranslated region of a gene DMPK. It is not known how the expansion of this repeat causes the pathophysiology of DM. There are two main theories. One possibility is that expansion of the repeat affects the expression of DMPK and neighbouring genes. The other possibility is that the DMPK RNA with an expanded repeat interacts with cellular proteins to produce a gain-of-function mutation. We are actively investigating both possible mechanisms.

The Pearson Lab

Christopher E. Pearson completed a Ph.D. (McGill University, 1994) studying mammalian DNA replication and protein interactions with cruciform-DNAs, proceeded to a post-doc (Texas Medical Center) elucidating the newly identified disease-mutation of trinucleotide repeat instability. During this time, Christopher discovered the elusive slipped-strand DNAs. Christopher is a Senior Scientist at The Hospital for Sick Children, Department of Genetics; an Associate Professor at the University of Toronto, Department of Medical Genetics & Microbiology; and a member of the Canadian Genetic Diseases Network.

The Pearson Lab studies the molecular mechanisms involved in genetic mutations in trinucleotide repeat sequences.  Instability (i.e., expansions) of trinucleotide repeats are responsible for numerous neurological, neurodegenerative, and neuromuscular disorders including myotonic dystrophy (the most common form of muscular dystrophy), Huntington’s disease and fragile X syndrome (the most common form of inherited mental retardation). Our research focus is identifying cis-elements and trans-factors as well as cellular mechanisms (i.e., DNA repair, DNA replication, and epigenetics) that are involved in disease-associated repeat instability. We use molecular, cellular and chromosomal systems including primate models, patient cells and tissues and transgenic mice in our studies.

Other USA Labs working on Myotonic Dystrophy

Andy Berglund – University of Oregon
Tom Cooper – Baylor College of Medicine
Ralph Krahe – MD Anderson Cancer Center
Mani Mahadevan – University of Virginia
Glenn Morris – Wolfson Center for Inherited Neuromuscular Disease
Jack Puymirat – University of Laval
Laura Ranum – University of Minnesota
Sita Reddy – Keck School of Medicine of USC
Maurice Swanson – University of Florida
Charles Thornton – University of Rochester Medical Center
Nikolai Timchenko – Baylor College of Medicine


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1 thought on “The Laboratories….. Researchers working on Myotonic Dystrophy

  1. Would any researchers working on Myotonic Dystrophy like to be involved with the Calendar for 2018,.?
    A picture of your researchers should reach the Myotonic Dystrophy Support Group by June 2017.
    An email of interest would be advised as there are only 12 months in a year!
    The places went quickly last year. The calendars will be small than last time and will be available at IDMC11. or from MDSG Office in the UK. mdsg@tesco.net

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