Dr. Andras Nagy’s laboratory and Dr. Timo Otonkoski’s laboratory (Biomedicum Stem Cell Center, University of Helsinki), in collaboration with researchers in Canada and Europe, have identified genetic abnormalities associated with reprogramming adult cells to induced pluripotent stem cells (iPSCs), published this month in Nature.

They compared copy number variations (CNVs) of different passages of human iPSCs with the original fibroblast cells and human ES cells and found that early passage iPSCs contained a higher number of deletions than late passage iPSCs and the other cell types. These deletions are generated during the reprogramming process, and most are lost with subsequent passages due to strong negative selection pressure.

Several copy number changes were found to be located within genes and regions essential for maintaining an undifferentiated state. As well, deletions occurred more frequently in common fragile sites (CFSs) in reprogrammed iPSCs.

The findings demonstrate that the reprogramming process is associated with high mutation rates and give researchers new insights into the reprogramming process, and will help make future applications of stem cell creation and subsequent use safer.

Copy number variation and selection during reprogramming to pluripotency. Hussein SM, Batada NN, Vuoristo S, Ching RW, Autio R, Närvä E, Ng S, Sourour M, Hämäläinen R, Olsson C, Lundin K, Mikkola M, Trokovic R, Peitz M, Brüstle O, Bazett-Jones DP, Alitalo K, Lahesmaa R, Nagy A, Otonkoski T. Nature. 2011 Mar 3. [Abstract]

Congratulations to the McEwen Centre's Dr. Mansoor Husain on being appointed the new Director of the Toronto General Research Institute. He will officially begin this role in May 2011.

As a specialist in cardiovascular disease and nuclear cardiology, Dr. Husain brings outstanding clinical and research credentials to the role. He is currently Director of Research at the Peter Munk Cardiac Centre at UHN and Director of the Heart & Stroke/Richard Lewar Centre of Excellence at the University of Toronto.

Congratulations to Dr. Molly Shoichet, who has been appointed to the Province's highest honour, in recognition of her contribution to regenerative medicine--designing strategies and materials to help the body heal itself after traumatic injury, in particular to the brain and spinal cord.

The Order of Ontario is awarded to Ontarians for excellence and achievement in any field. About 25 people are invested into the Order of Ontario each year, and are considered an example of excellence to all Ontarians.

The next Stem Cell Rounds, Hot Topics in Mesenchymal Stem Cells, will take place on Tuesday, March 29, 2011 at 4:30 pm in Room 6, Tanz Neuroscience Building. It will include lectures by Dr. Sevan Hopyan (Hopsital for Sick Children - HSC), Kristine McKenzie (Dr. Aubin's lab, UT), and Jason Rockel (Dr. Alman's lab, HSC).

The 4th Annual Regenerative Medicine Symposium will take place on April 6-7, 2011, hosted by the Training Program in Regenerative Medicine (TPRM) and its sponsors. This symposium will include keynote lectures from Drs. Peter Zandstra and Connie Eaves (UBC). For more information, visit the TPRM website.

Congratulations to McEwen researchers for their success in the latest round of operating grants awarded by the Heart and Stroke Foundation of Ontario. Drs. Mansoor Husain and Peter Zandstra were awarded renewals of their grants.