Participation & More We are enrolling patients and their families into our studies on congenital myopathies, including centronuclear myopathy (CNM)/X-linked myo-

tubular myopathy (XLMTM), central core disease (CCD), congenital fiber type disproportion

(CFTD), multiminicore disease (MmD), myofibril-lar myopathy (MFM), nemaline myopathy (NM), rigid spine muscular dystrophy (RSMD) and un-

defined neuromuscular diseases. For more infor-mation about our research and the topics in this newsletter, to request to be removed from the mailing list, or to inquire about making a dona-

tion, please visit our website at www.childrenshospital.org/research/beggs,

return the comment card, or contact our new research coordinator:

Lindsay Swanson, MS, CGC Boston Children’s Hospital 3 Blackfan Circle, CLSB 15

Boston, MA 02115 Ph: 617-919-2169

Beggs Newsletter Spring 2013 * Volume 8

Apologies to all for this late “New Year’s” newsletter! The past year has been filled with transitions, challenges, and some great pro-gress. We said goodbye to Elizabeth DeChene, who moved to Phila-delphia to take a great new job and be closer to family, and hello to Lindsay Swanson, who has stepped into Elizabeth’s shoes with great enthusiasm and aplomb. The economy has been a particular chal-lenge, with funding from foundations, federal grants, and philan-thropic sources all contracting. Thanks so much to everybody who has contributed to support the lab. Your donations make a big difference and your support means the world to us! We have also been incredibly fortunate to benefit from fellowship grants that several senior postdocs successfully competed for, and I am pleased to report that, despite sequestration, our long standing NIH grant has recently been renewed and another new proposal is currently under review. Most importantly, none of this has stopped us from making progress! 2012 was a banner year with 16 publications de-scribing work from the Beggs Lab. In October, we presented data at the World Muscle Society meeting in Perth, Australia on exciting new gene and protein therapies for myotubular myopathy, new zebrafish models for congenital myopathies, and also a new genetic cause for centronuclear myopathy. Just this last month, the protein therapy manuscript, and a seminal paper describing our new mouse model for multi-minicore myopathy due to selenoprotein N muta-tion were published. Together with your support and collaboration, we look forward to continuing our work to make a difference for all our families with congenital myopathies.

From the Beggs Congenital Myopathy Research Program at Boston Children’s Hospital & Harvard Medical School

Happy Spring!

HAPPY NEW YEAR!

We welcome genetic counselor Lindsay Swanson who joined the Beggs Lab in July after receiving her Master’s Degree from the University of Minnesota.

UPCOMING EVENTS The MTM-CNM Family Conference is July 26-28 in Minneapolis, MN, USA (www.mtm-cnm.com)

For more info, email warderin@comcast.net

The 5th Nemaline Myopathy Convention – July 26-28 in St. Catharines, Ontario, Canada. Please

see www.nemaline.org for details.

Our research with zebrafish continues to help our understanding of the congenital myopathies. Zebrafish make a won-derful model for muscle disease because they breed and develop quickly, and their muscle structure is remarkably similar to humans. Dr. Vandana Gupta’s research on identifying genes that result in congenital muscle disease recently identified zebrafish with a mutation in the laminin-α2 (merosin) gene. Laminin-α2 is a protein that provides stability to muscle structure. The fish without laminin-α2 show severe skeletal muscle dystrophy with eye and brain abnormalities, just like humans who have been diagnosed with merosin-deficient congenital muscular dystrophy (MDC1A). Vandana is collabo-rating with members of the Kunkel Lab to screen for drugs that allow these fish to develop normally and is now develop-ing drug screens with ryanodine receptor (RYR1) mutated fish, which model human mini-core myopathy.

Vandana has also focused her research on α-actinins. These are actin-binding proteins that make up a family of very similar proteins. The α-actinins show identical activities in most in vitro (“test tube”) experiments and appear to be able to substitute for each other in laboratory experiments. Vandana’s zebrafish studies showed that α-actinins work in differ-ent parts of the bodies of zebrafish and express at different times during zebrafish develop-ment. Loss of α-actinin-2 caused skeletal muscle and heart abnormalities in developing fish that could not be rescued by highly similar α-actinin-3. These studies showed that even though α-actinins have similar genetic sequence, the different forms have evolved differ-ently to optimize their function.

There is much more activity in the lab on this front. In two new projects just getting started, Dr. Ozge Ceyhan is generating transgenic actin zebrafish for their use in developing

therapies for nemaline myopathy. Graduate student Laura Smith has been actively involved in developing zebrafish mod-els for centronuclear and minicore myopathies caused by de-fects in the BIN1, DNM2, and SEPN1 genes.

NEWS FROM THE TANK

HAPPY SPRING!

THE CLARITY CHALLENGE COMPLETED! Developing Best Practices for Whole Genome Sequencing

SPRING 2013 * VOLUME 8 PAGE 2

At the American Society of Human Genetics conference in San Francisco in November, Drs. Catherine Brownstein and Alan Beggs held a press conference to announce the winners of the CLARITY Challenge, which was introduced in our 2011 newsletter. 25 contestants from around the world worked to identify the genetic mutations in three families whose ge-nomes were sequenced. The contest resulted in the discovery of the genetic basis for conditions in two of the families, including AJ Foye, who has centronuclear myopathy. The contestants were also asked to report their findings in a way that was most meaningful to clinicians, patients, and families. The three finalists were the Division of Clinical Genetics at Brigham and Women’s Hospital, the University of Iowa, and a combined team from CeGaT, Genomatix, and University Hospital Bonn, in Germany.

The Beggs Lab is actively using whole genome sequencing (WGS) in their approaches to learning more about the genetics of the congenital myopa-thies. In the past year, three new genes discovered by WGS were published by the Beggs Lab. The new genes are:

1. MEGF10 causing multiminicore disease (Boyden et al.) 2. CCDC78 causing centronuclear myopathy with minicores (Majczenko et al.) 3. GTDC2 causing a form of muscular dystrophy (Manzini et al.)

At the World Muscle Society Conference in Perth, Australia in October, Dr. Ozge Ceyhan announced the discovery of mutations in the titin gene (TTN) in patients with centronuclear myopathy including in AJ Foye who was part of the CLARITY Challenge. This was the first time a link between TTN and CNM has been found. For the Foye family, they finally have an answer for why their son AJ has centronuclear myopathy. This is an exciting breakthrough for centronuclear myopathy research and for families like the Foyes who have been looking for answers for over a decade.

Catherine Brownstein, Alan Beggs, and Sarah Foye with the team from University of Iowa at the CLARITY Chal-lenge award presentation in San Francisco, CA

Laura Smith presents her work on zebrafish models of centronucle-ar myopathy at the 2013 MDA Scientific Conference on April 23rd

PLANNING A VISIT TO BOSTON THIS YEAR?

We would love to meet you and give you a tour

of the lab!

A MOUSE MODEL FOR COFILIN-2 RESEARCH

RESOURCES FOR PATIENTS

General Resources:

Muscular Dystrophy Association (www.mdausa.org)

GeneReviews (www.genereviews.org)

Genetics Home Reference (http://ghr.nlm.nih.gov/) Connections to Families:

Congenital Muscle Disease International Registry (www.cmdir.org)

Facebook and Yahoo Groups

My MDA at mymda.mda.org Search under: CFTD, Minicore, Myopathy, Myotubular,

or Nemaline Condition Specific Resources:

CFTD The Caytlon Wheeler Foundation

(www.caytlonwheeler.org)

CNM/MTM The Joshua Frase Foundation (www.joshuafrase.org)

The Information Point for CNM/MTM (www.centronuclear.org.uk) MTM Resource Group (www.mtmrg.org) Myotubular Trust (www.myotubulartrust.com)

NM The NM Support Group (www.nemaline.org)

PAGE 3 SPRING 2013 * VOLUME 8

In 2007, researchers from the Beggs Laboratory identified cofilin-2 (CFL2) to be the sixth gene mutated in nemaline myopathy with minicores. This year, Dr. Pankaj Agrawal and his team developed a mouse model with changes or altera-tions in the CFL2 gene. Mutations of CFL2 result in reduced amounts or altered forms of cofilin-2, a protein important for maintaining the function of muscle. A mouse model was created because this animal can help us to understand the mechanism for how changes in CFL2 cause congenital myopathy. We were able to decrease CFL2 gene expression in mice and show that these mice had symp-toms similar to those observed in patients with severe muscle weakness. These research findings were published in the journal Human Molecular Genetics (Agrawal et al.). These studies have established the role of cofilin-2 in maintain-ing muscle function. We hope to continue studying these “knockout” or de-creased CFL2 mice for clues as to the function of cofilin-2 in maintaining healthy muscle. Additionally, this year we collaborated with a research group in the Netherlands to describe the second known family with a mutation of CFL2 (Ockleoen et al.).

CLINICAL GENETIC TESTING

Commercial genetic testing is now available for many of the genes associated with the congenital myopathies. More information is available at www.ncbi.nlm.nih.gov/gtr/

*Full sequencing and specific testing for the exon 55 deletion, a mutation more common in the Ashkenazi Jewish population, are both available

DISEASE ASSOCIATED GENES

(% of cases with mutations in given gene)

CCD RYR1

(>90%)

CFTD TPM3

(20-30%)

RYR1

(?)

ACTA1 (6%)

SEPN1/MYH7

TPM2 (rare)

CNM DNM2 (?) RYR1 (?) BIN1 (rare)

TTN (?)

XLMTM MTM1 (>80%)

MmD/ RSMD

SEPN1

(30-50%)

RYR1

(?)

ACTA1 (rare)

NM ACTA1

(15-25%)

TPM2/ TPM3

(<10%)

NEB (~50%)*

TNNT1/CFL2

(rare)

WE WOULD LOVE TO HEAR FROM YOU!

For more information about our research and the topics in this news-

letter or for suggestions on future topics, please return this card to:

Lindsay Swanson, MS, CGC Boston Children’s Hospital 3 Blackfan Circle, CLSB 15

Boston, MA 02115 Ph: 617-919-2169

COMMENT CARD

NAME OF PERSON COMPLETING CARD:______________________________________________

QUESTION/COMMENT:___________________________________________________________

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Dr. Jeffrey Widrick joins the Beggs Lab from Spaulding Rehabilitation

Hospital, Boston. Dr. Widrick’s background is in muscle physiolo-gy. His research uses isolated mus-cle and single muscle cells to understand how mechanisms un-derlying contrac-

tion are altered in neuromuscular disease.

RECENT KEY PUBLICATIONS Gupta V, et al. α-Actinin-2 deficiency results in sarcomeric defects in zebrafish that cannot be rescued by α-actinin-3 revealing functional differences between sarco-

meric isoforms. FASEB J. 2012 May;26(5):1892-908. Agrawal PB, et al. Normal myofibrillar development followed by progressive sarcomeric disruption with actin accumulations in a mouse Cfl2 knockout demonstrates

requirement of cofilin-2 for muscle maintenance. Hum Mol Genet. 2012 May 15;21(10):2341-56. Boyden SE, et al. Mutations in the satellite cell gene MEGF10 cause a recessive congenital myopathy with minicores.Neurogenetics. 2012 May;13(2):115-24. Böhm J, et al. Mutation spectrum in the large GTPase dynamin 2, and genotype-phenotype correlation in autosomal dominant centronuclear myopathy. Hum Mutat.

2012 Jun;33(6):949-59. Ockeloen CW, et al. Congenital myopathy caused by a novel missense mutation in the CFL2 gene. Neuromuscul Disord. 2012 Jul;22(7):632-9. Biancalana V, et al. Clinical utility gene card for: Centronuclear and myotubular myopathies. Eur J Hum Genet. 2012 Oct;20(10). Dowling JJ, et al. Myotubular myopathy and the neuromuscular junction: a novel therapeutic approach from mouse models. Dis Model Mech. 2012 Nov;5(6):852-9. Majczenko K, et al. Dominant mutation of CCDC78 in a unique congenital myopathy with prominent internal nuclei and atypical cores. Am J Hum Genet. 2012 Aug 10;91

(2):365-71. Lawlor MW, et al. Myotubularin-deficient myoblasts display increased apoptosis, delayed proliferation, and poor cell engraftment. Am J Pathol. 2012 Sep;181(3):961-8. Gupta VA, et al. A splice site mutation in laminin-α2 results in a severe muscular dystrophy and growth abnormalities in zebrafish. PLoS One. 2012;7(8):e43794. Manzini MC, et al. Exome sequencing and functional validation in zebrafish identify GTDC2 mutations as a cause of Walker-Warburg syndrome. Am J Hum Genet. 2012

Sep 7;91(3):541-7. Grange RW, et al. Muscle function in a canine model of X-linked myotubular myopathy. Muscle Nerve. 2012 Oct;46(4):588-91.

Beggs Laboratory Boston Children’s Hospital

3 Blackfan Circle CLSB 15

Boston, MA 02115

RECENT EVENTS

Congratulations to Elizabeth DeChene, MS, CGC, who has started a new po-sition at Children’s Hospital of Philadelphia, and to Christine Mahoney, our previous research assistant, who is pursuing her master’s degree in Organi-zational Psychology at Columbia University. Congratulations also to Marissa Viola who is pursuing her PhD at the University of Rhode Island. A warm welcome to Dr. Ozge Ceyhan, a new post-doctoral research fellow, to Dr. Huan Ling Wang who is a visiting associate professor from Huazhong Agri-cultural University in China, to Dr. Shideh Kazerounian, a senior research fellow, and to Nicholas Marinakis, a new research assistant in the lab.

Beggs Newsletter Spring 2013 * Volume 8