TCP Logo Toronto Centre for Phenogenomics    
Transgenic Core

The TCP Transgenic Core (TG Core) is an amalgamation of the Transgenic Facilities at Mount Sinai Hospital and The Hospital for Sick Children. These facilities have been operating since early 1990s and have pioneered innovative technologies such as the production of mouse ES cell chimeras using the aggregation method and Tetraploid Complementation Assay.1-3 See more recent examples of this technology's applications in following selected publications 4-11 . The TCP Transgenic core continues to maintain a close affiliation with the laboratories of Dr. Janet Rossant and Dr. Andras Nagy.

The TCP Transgenic Core staff were among the organizers of very successful 8th International Transgenic Technology Meeting, held in Toronto in October 2008 on behalf of the International Society for Transgenic Technologies (blog1, blog 2, blog 3). TCP Transgenic Core together with Dr. Andras Nagy laboratory hosted The Tetraploid Complementation Assay workshop for TT2008 participants.

The TCP Transgenic Core provides a range of services generating Genetically Engineered Mouse Models (GEMM) for investigators from TCP member hospitals, the University of Toronto, external academic and for-profit institutions. We offer transgenic production, gene targeting, and generation of chimeras. Genetically modified ES cells are provided by local Toronto ES cell facilities, The International Gene Trap Consortium including the Gene Trap Resource at The Centre for Modeling Human Disease (CMHD) and International Knockout Mouse Consortium (IKMC). CMHD gene trap and NorCOMM targeted clones are distributed by the Canadian Mouse Mutant Repository (CMMR) located at TCP.

Since 2011 TCP Transgenic Core participates in NorCOMM2 and IKMC resources for phenotyping -- effort co-ordinated by the International Phenotyping Consortium (IMPC). Based on the clones that completed breeding 62% transmitted through the germline from all attempted clones (February 2013 update).

Germline transmission (GLT) rate from targeted C57BL/6 ES cells (April 2014 update)

Parental ES cell line # clones attempted # clones with >50%
male chimeras (%)
# GLT clones # clones with breeding in progress % GLT (per # clones with complete breeding) % GLT (per all clones attempted)
JM8 variants 81 70 (86%) 42 6 66% 52%
JM8A variants 313 280 (89%) 129 10 48% 41%
VGB6 42 33 (79%) 22 4 76% 52%
C2* 117 108 (92%) 85 1 79% 73%
TOTAL 553 491 (89%) 278 21 59% 50%

* C57BL/6NTac-C2 is the ES cell line used by TCP Transgenic Core, the data from our gene targeting services using C2 are combined with NorCOMM and NorCOMM2 production pipelines.

See our publication 12 for more details:

C57BL/6N ES cell chimeras generated by aggregation with outbred ICR host embryos

TCP Transgenic Core Services »

Selected References

  1. Nagy, A., E. Gocza, E. Merentes-Diaz, V.R. Prideaux, E. Ivanyi, M. Markkula and J. Rossant. Embryonic stem cells alone are able to support fetal development in the mouse. Development 1990 110, 815-821. (
  2. Nagy, A., J. Rossant, R. Nagy, W. Abramow-Newerly and J.C. Roder Derivation of completely cell culture-derived mice from early passage embryonic stem cells. Proc. Natl. Acad. Sci. USA 1993 90, 8424-8428. (
  3. Wood, S.A., N.D. Allen, J. Rossant, A. Auerbach and A. Nagy. Non-injection methods for the production of embryonic stem cell-embryo chimaeras. Nature, 1993, 365, 87-89.
  4. Kunath T, Gish G, Lickert H, Jones N, Pawson T, Rossant J. Transgenic RNA interference in ES cell-derived embryos recapitulates a genetic null phenotype. Nat Biotechnol. 2003 May; 21(5):559-61.
  5. Vintersten K, Monetti C, Gertsenstein M, Zhang P, Laszlo L, Biechele S, Nagy A. Mouse in red: Red fluorescent protein expression in mouse ES cells, embryos, and adult animals. genesis. 2004 Dec 9;40(4):241-246
  6. Lickert H, Cox B, Wehrle C, Taketo MM, Kemler R, Rossant J.. Dissecting Wnt/beta-catenin signaling during gastrulation using RNA interference in mouse embryos. Development. 2005 Jun; 132(11):2599-609
  7. Takeuchi JK, Mileikovskaia M, Koshiba-Takeuchi K, Heidt AB, Mori AD, Arruda EP, Gertsenstein M, Georges R, Davidson L, Mo R, Hui CC, Henkelman RM, Nemer M, Black BL, Nagy A, Bruneau BG. Tbx20 dose-dependently regulates transcription factor networks required for mouse heart and motoneuron development. Development. 2005 May; 132(10):2463-74
  8. George S.H.L., Gertsenstein M., Vintersten K., Korets-Smith E., Murphy J., Stevens M.E., Haigh J.J., and Nagy A. (2007) Developmental and adult phenotyping directly from mutant embryonic stem cells. 2007 PNAS 10.1073/pnas.0609277104
  9. Takeuchi JK, Lickert H, Bisgrove BW, Sun X, Yamamoto M, Chawengsaksophak K, Hamada H, Yost HJ, Rossant J, Bruneau BG. Baf60c is a nuclear Notch signaling component required for the establishment of left-right asymmetry.
    Proc Natl Acad Sci U S A. 2007 Jan 16; 104(3):846-51
  10. Woltjen K, Michael IP, Mohseni P, Desai R, Mileikovsky M, Hämäläinen R, Cowling R, Wang W, Liu P, Gertsenstein M, Kaji K, Sung HK, Nagy A. piggyBac transposition reprograms fibroblasts to induced pluripotent stem cells. Nature 2009 Apr 9; 458(7239):766-70
  11. Cox BJ, Vollmer M, Tamplin O, Lu M, Biechele S, Floss T, Gertsenstein M, van Campenhout C, Kühn R, Wurst W, Lickert H, Rossant J. Phenotypic annotation of the mouse X chromosome. Genome Res. 2010 Aug; 20(8):1154-64
  12. Gertsenstein M, Nutter LM, Reid T, Pereira M, Stanford WL, Rossant J, Nagy A. Efficient generation of germ line transmitting chimeras from C57BL/6N ES cells by aggregation with outbred host embryos. PLoS One. 2010 Jun 22; 5(6):e11260

For more information, please contact:

Marina Gertsenstein
The Transgenic Core
The Toronto Centre for Phenogenomics
25 Orde Street, Toronto, ON M5T 3H7
Tel: 647-837-5811 x4302
Fax: 647-837-5834


TCP Logo