Professor Susannah L. Varmuza

Susannah L. Varmuza

Professor Emerita


St. George (downtown)

CSB Appointment


Research Areas

Developmental Biology, Molecular Biology


Ph.D. McMaster University, 1985

Primary Undergraduate Department

Cell & Systems Biology

Graduate Programs

Cell & Systems Biology

Academic or Administrative Appointments

Associate Chair for Undergraduate Studies

Research Description

My research area is Epigenetics, with a focus on genomic imprinting in mammals and its impact on development.

Contact Information

Office Phone: 416-978-2759
Office: RW537A
Lab: RW537
Lab Phone: 416-946-7220

Mailing Address

Department of Cell & Systems Biology
University of Toronto
25 Harbord St.
Toronto, ON M5S 3G5



Positive regulation of TRAF6-dependent innate immune responses by protein phosphatase PP1-γ

Opaluch AM, Schneider M, Chiang CY, Nguyen QT, Maestre AM, Mulder LC, Secundino I, De Jesus PD, König R, Simon V, Nizet V, MacLeod G, Varmuza S, Fernandez-Sesma A, Chanda SK
2014, PloS one, 9, e89284, 24586659

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PPP1CC2 can form a kinase/phosphatase complex with the testis-specific proteins TSSK1 and TSKS in the mouse testis

MacLeod G, Shang P, Booth GT, Mastropaolo LA, Manafpoursakha N, Vogl AW, Varmuza S
2014, Reproduction (Cambridge, England), 147, 1-12, 24088291

The imprinted polycomb group gene Sfmbt2 is required for trophoblast maintenance and placenta development

Miri K, Latham K, Panning B, Zhong Z, Andersen A, Varmuza S
2013, Development (Cambridge, England), 140, 4480-9, 24154523

The application of proteomic approaches to the study of mammalian spermatogenesis and sperm function

Macleod G, Varmuza S
2013, The FEBS journal, 280, 5635-51, 23902417

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Tandem affinity purification in transgenic mouse embryonic stem cells identifies DDOST as a novel PPP1CC2 interacting protein

MacLeod G, Varmuza S
2012, Biochemistry, 51, 9678-88, 23140390

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Recent acquisition of imprinting at the rodent Sfmbt2 locus correlates with insertion of a large block of miRNAs

Wang Q, Chow J, Hong J, Smith AF, Moreno C, Seaby P, Vrana P, Miri K, Tak J, Chung ED, Mastromonaco G, Caniggia I, Varmuza S
2011, BMC genomics, 12, 204, 21510876

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Loss of protein phosphatase 1c{gamma} (PPP1CC) leads to impaired spermatogenesis associated with defects in chromatin condensation and acrosome development: an ultrastructural analysis

Forgione N, Vogl AW, Varmuza S
2010, Reproduction (Cambridge, England), 139, 1021-9, 20385779

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Metakaryotic stem cell lineages in organogenesis of humans and other metazoans

Gostjeva EV, Koledova V, Tomita-Mitchell A, Mitchell M, Goetsch MA, Varmuza S, Fomina JN, Darroudi F, Thilly WG
2009, Organogenesis, 5, 191-200, 20539738

Identification of potentially damaging amino acid substitutions leading to human male infertility

Kuzmin A, Jarvi K, Lo K, Spencer L, Chow GY, Macleod G, Wang Q, Varmuza S
2009, Biology of reproduction, 81, 319-26, 19369647

Imprinting and extraembryonic tissues-mom takes control

Miri K, Varmuza S
2009, International review of cell and molecular biology, 276, 215-62, 19584014

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The PcG gene Sfmbt2 is paternally expressed in extraembryonic tissues

Kuzmin A, Han Z, Golding MC, Mann MR, Latham KE, Varmuza S
2008, Gene expression patterns : GEP, 8, 107-16, 18024232

A testis specific isoform of endophilin B1, endophilin B1t, interacts specifically with protein phosphatase-1c gamma2 in mouse testis and is abnormally expressed in PP1c gamma null mice

Hrabchak C, Henderson H, Varmuza S
2007, Biochemistry, 46, 4635-44, 17381077

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Identification of the spermatogenic zip protein Spz1 as a putative protein phosphatase-1 (PP1) regulatory protein that specifically binds the PP1cgamma2 splice variant in mouse testis

Hrabchak C, Varmuza S
2004, The Journal of biological chemistry, 279, 37079-86, 15226296

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Epigenetics and the renaissance of heresy

Varmuza S
2003, Genome / National Research Council Canada = Génome / Conseil national de recherches Canada, 46, 963-7; discussion 968-73, 14663513

Protein phosphatase 1cgamma is required in germ cells in murine testis

Oppedisano-Wells L, Varmuza S
2003, Molecular reproduction and development, 65, 157-66, 12704726

Increased recombination frequency showing evidence of loss of interference is associated with abnormal testicular histopathology

Varmuza S, Ling L
2003, Molecular reproduction and development, 64, 499-506, 12589662

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Development to blastocyst is impaired when intracytoplasmic sperm injection is performed with abnormal sperm from infertile mice harboring a mutation in the protein phosphatase 1cgamma gene

Davies T, Varmuza S
2003, Biology of reproduction, 68, 1470-6, 12606345

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