About Sickkids
About SickKids

Stephen Meyn, MD, PhD, FRCPC, FACMG

The Hospital for Sick Children
Staff Geneticist, Division of Clinical and Metabolic Genetics
Department of Paediatrics

Research Institute
Project Investigator
Research Institute

University of Toronto
Molecular Genetics, Paediatrics

Phone: 416-813-8485
Fax: 416-813-4931
e-mail: stephen.meyn@sickkids.ca

Brief Biography

Dr. Meyn received his MD and PhD degrees from New York University, then completed an internship and residency in paediatrics at the University of California, San Francisco.  He subsequently trained in medical genetics and molecular genetics at the National Institutes of Health (USA) before joining the faculty of the Yale School of Medicine. In 1998 Dr. Meyn was recruited to SickKids and the University of Toronto.

Dr. Meyn is a clinician-scientist and staff geneticist in the Division of Clinical and Metabolic Genetics at SickKids as well as a Senior Scientist and past Head of SickKids’ Program in Genetics & Genome Biology.  He also is a Professor in the Departments of Paediatrics and Molecular Genetics at the University of Toronto.  

Clinical Activities

Dr. Meyn is the principal staff geneticist for the SickKids Cancer Genetics Program.  He also is co-director of the Centre for Genetic Medicine’s Genome Clinic, a personalized genetic medicine project which pilots the diagnostic and predictive uses of genomics in clinical care.  (http://www.sickkids.ca/Centres/Centre-Genetic-Medicine/The-Genome-Clinic/FAQs/Index.html)

Research Interests

  • DNA repair, genetic recombination and telomere biology
  • The molecular pathology of chromosome instability syndromes
  • The development and implementation of genomic medicine

Research Activities

Dr. Meyn’s research interests range from the bench to the bedside.  His basic science research program focuses on understanding the molecular networks human cells use to protect their genomes from DNA damage. These networks are complex and involve DNA repair, genetic recombination, alterations in the cell cycle, and programmed cell death. His laboratory uses a combination of somatic cell genetics, molecular genetics and start of the art imaging techniques to study how human cells mobilize their responses to induced DNA damage and how DNA damage response proteins interact with each other and with DNA at sites of DNA damage.

The long term goal of translational research in Dr. Meyn’s laboratory is to better understand the molecular pathology of ataxia-telangiectasia, Fanconi anemia and other chromosome instability syndromes, inherited human diseases in which the cellular defenses against genomic damage have been compromised. This work is currently focused on determining the role played by dysfunctional telomeres in the clinical phenotype of these diseases.  

Dr. Meyn’s clinical research activities center around the SickKids’ Genome Clinic. The Genome Clinic is designed to serve as a test bed for multiple studies related to the implementation of whole genome sequencing in the routine clinical care of children. This project, the first of its kind in Canada, supports a broad range of research activities, involving bioinformatics, clinical diagnostics, medical genetics, genetic counselling, bioethics and health economics. As one of the co-directors of the Genome Clinic, Dr. Meyn is particularly interested in the predictive uses of whole genome/exome sequencing and the ethical implementation of genomic medicine.


Bowdin S, Monfarad N, Cohn RD, Hayeems R and Meyn MS. The Genome Clinic: Developing and evaluating a pediatric model for individualized genomic medicine. Clinical Genetics doi: 10.1111/cge.12579. (2015)

Komosa M, Root HA and Meyn MS.  Quantitative visualization and analysis of extrachromosomal telomeric repeat DNA in individual human cells using Halo-FISH. Nucleic Acids Res doi: 10.1093/nar/gkv091 (2015)

Ghemlas I, Li H , Zlateska B, Klaassen R, Fernandez CV, Yanofsky RA, Wu J, Pastore Y, Silva M, Lipton JH, Brossard J, Brunon M, Abish S, Steele M, Sinha R, Belltrutti M, Breaky V, Jardine L, Goodyear L, Sung L, Dhanraj S, Reble E, Wagner A, Beyene J, Ray P, Meyn MS, Cada M, Dror Y. Improving diagnostic precision, care and syndrome definitions using NGS for the inherited bone marrow failure syndromes. J Med Genet: doi: 10.1136/jmedgenet-2015-103270 (2015)

Boycott K, Hartley T, Adam S, Bernier F, Chong K, Fernandez B, Friedman JM, Geraghty M, Hume H, Knoppers,  Laberge A-M, Majewski J, Mendoza-Londono R, Meyn MS, Michaud J, Nelson TN, Richer J, Sadikovic B, Skidmore DL, Stockley T, Taylor S, van Karnebeek C, Zawati M, Julie Lauzon J, Armour C, on behalf of the Canadian College of Medical Geneticists. The clinical application of genome-wide sequencing for monogenic diseases in Canada - Position Statement of the Canadian College of Medical Geneticists. J Med Genet doi:10.1136/jmedgenet-2015-103144 (2015)

Shlien A, Campbell  BB, de Borja R, Alexandrov LB, Merico D, Wedge D, van Loo P, Tarpey P, Coupland P, Behjati S, Pollett A, Lipman T, Heidari A, Deshmukh S, Avitzur N, Meier B, Gerstung M, Hong Y, Merino DM, Ramakrishna M, Remke M, Arnold R, Panigrahi GB, Thakkar NP, Hodel KP, Henninger EE, Göksenin AY, Bakry D, Charames GS, Druker H, Lerner-Ellis J, Mistry M, Dvir R, Grant R, Elchasid R, Farah R, Taylor GP, Nathan PC, Alexander S, Shachar SB,  Ling SC, Gallinger S, Constantini S, Dirks P, Huang A, Scherer SW, Grundy RG, Durno C, Aronson M, Gartner A, Meyn MS, Taylor MD, Pursell ZF, Pearson CE, Malkin D, Futreal PA, Stratton MR, Bouffet E, Hawkins C, Campbell PJ and Tabori U. Hereditary and Somatic Mutations of Replication Error Repair Genes Result in Rapid Onset of Ultra Hypermutated Cancers. Nature Genetics doi:10.1038/ng.3202 (2015)

Anderson, J, Hayheems R, Szego M, Hayeems R, Shuman C, Monfared N, Bowdin S, Zlotnik-Shaul R and Meyn MS. Predictive Genetic Testing for Adult-Onset Disorders in Minors: A Critical Analysis of the Arguments For and Against the 2013 ACMG guidelines. Clinical Genetics (2014 Jul 21. doi: 10.1111/cge.12460).

Metcalf JL, Bradshaw PS, Komosa M, Greer SN, Meyn MS, and Ohh M. K63-ubiquitylation of VHL by SOCS1 mediates DNA double-strand break repair. Oncogene 33: 1055-1065 (2014)

Bowdin S, Ray P, Cohn RD, and Meyn MS. The Genome Clinic: A multidisciplinary approach to assessing the opportunities and challenges of integrating genomic analysis into clinical care. Hum Mutation 35: 513-519 (2014).

Girdea M, Sergiu Dumitriu S, Bowdin S, Boycott K, Chenier S, Chitayat D, Faghfoury H, Meyn MS, Ray PN, So J, Stavropoulos J, Brudno M. PhenoTips: patient phenotyping software for clinical and research use. Human Mutation 34:1057-65 (2013).

Weemaes CMR, van Tol MJD, Wang J, van Ostaijen-ten Dam MM, van Eggermond MCJA, Thijssen PE, Aytekin C, Brunetti- Pierri N, van der Burg M, E. Davies EG, Ferster A, Furthner D, Gimelli G, Gennery A, Kloeckener-Gruissem B, Meyn S, Powell C, Reisli I, Schuetz C, Schulz A, Shugar A, van den Elsen PJ, van der Maarel SM. Heterogeneous clinical presentation in ICF syndrome: correlation with underlying gene defect. Eur J Hum Genet 21: 1219-1225 (2013)

Williams, B, Meyn, MS, Hitzler, J. Transient leukemia in newborns without Down syndrome - diagnostic and management challenges.  J Ped Hem Onc 33: e261-3 (2011)  

Spencer, E,  Ramsey, J, Mikhail, F, Fu. C, Vijzelaar, R,  Zackai, E, Ferret, H,  Meyn, MS, Shugar, S,  Kivirikku, S,  Pöyhönen, M, and Messiaen, L. Identification of copy number changes affecting the SPRED1 gene using RT-PCR, Multiplex Ligation-dependent Probe Amplification and Quantitative PCR Am J Med Genet 155A: 1352-1359 (2011)

Differential DNA damage responses bias human hematopoietic stem cells towards p53-mediated apoptosis.  Milyasky M, Gan OI, Trottier M, Nota F, Lechman E, Hermans KG, Eppert K, Ornatsky O, Meyn MS, Dick JE. Cell Stem Cell 7:186-97 (2010)

Buchanan, JA, Carson AR, Chitayat D, Malkin D, Meyn MS, Ray PN, Shuman C, Weksberg R, Scherer SW. The cycle of genome-directed medicine. Genome Medicine (2009) 1:16

Demuth I, Jost A, Bradshaw PS, Anders M, Heinrich S, Digweed M, Meyn MS, Concannon P.  hSM1B/Apollo cooperates with TRF2 and stimulates ATM activation in response to ionizing radiation. DNA Repair 7: 1192-1201 (2008)

Weksberg, R, Stachon AC, Squire JA, Moldovan L, Bayani J, Meyn MS, Chow E, Bassett AS: Molecular characterization of deletion breakpoints in adults with 22q11 deletion syndrome. Hum Mol Genet 120: 837-45 (2007)  

Tanaka H, Mendonca MS, Bradshaw PS, Hoelz DJ, Malkas LH, Meyn MS, Gilley D: DNA damage induced phosphorylation of the human telomere associated protein TRF2.  Proc Natl Acad Sci, USA 102: 15539-44 (2005)

Bradshaw PS, Stavropoulos DJ, Meyn MS. Human telomeric protein TRF2 associates with genomic double-strand breaks as an early response to DNA damage. Nature Genetics 37: 193-198, 2005.

Wong JC, Alon N, Mckerlie C, Huang JR, Meyn MS, Buchwald M. Targeted disruption of exons 1 to 6 of the Fanconi Anemia group A gene leads to growth retardation, strain-specific microphthalmia, meiotic defects and primordial germ cell hypoplasia. Human Molecular Genetics 12: 2053-2076, 2003.

Houghtaling S, Timmers C, Noll M, Finegold MJ, Jones SN, Meyn MS, Grompe M. Epithelial cancer in Fanconi anemia complementation group D2 (Fancd2) knockout mice. Genes & Development 17:2021-2035, 2003.

Stavropoulos DJ, Bradshaw PS, Li X. Pasic I, Truong K, Ikura M, Ungrin M, Meyn MS. The Bloom syndrome helicase BLM interacts with TRF2 at telomeres in ALT cells and promotes telomere lengthening. Hum Mol Genet 11: pp 3135-3144, 2002.

Garcia-Higuera I, Taniguchi T, Ganesan S, Meyn MS, Timmers C, Grompe M, D'Andrea AD. DNA Damage-Induced Association of the Fanconi Anemia Protein, FANCD2, with BRCA1 Nuclear Foci. Molec. Cell 7: 249-262, 2001.

Fritz E, Elsea SH, Patel PI, Meyn MS. Overexpression of a human topoisomerase III protein alleviates multiple aspects of the ataxia-telangiectasia phenotype. Proc. Natl. Acad. Sci. USA 94: 4538-4542, 1997.

Xu Y, Bronson RT, Brainerd EE, Ashley T, Meyn MS, Baltimore D. Targeted disruption of Atm leads to g-rowth retardation, chromosomal fragmentation during meiosis, immune defects and thymic lymphoma. Genes & Development 10: 2211-2422, 1996.

Meyn MS. High spontaneous intrachromosomal recombination rates in ataxia-telangiectasia. Science 260: 1327-1330, 1993.