About the Authors

Susana M Chuva de Sousa Lopes

To whom correspondence should be addressed. E-mail: smc80@cam.ac.uk

¤ Current address: Hubrecht Institute, Developmental Biology and Stem Cell Reseach, Utrecht, The Netherlands

Affiliation The Wellcome Trust/Cancer Research UK Gurdon Institute, University of Cambridge, Cambridge, United Kingdom

Katsuhiko Hayashi

Affiliation The Wellcome Trust/Cancer Research UK Gurdon Institute, University of Cambridge, Cambridge, United Kingdom

Tanya C Shovlin

Affiliation The Wellcome Trust/Cancer Research UK Gurdon Institute, University of Cambridge, Cambridge, United Kingdom

Will Mifsud

Affiliation The Wellcome Trust/Cancer Research UK Gurdon Institute, University of Cambridge, Cambridge, United Kingdom

M. Azim Surani

Affiliation The Wellcome Trust/Cancer Research UK Gurdon Institute, University of Cambridge, Cambridge, United Kingdom

Anne McLaren

This article is dedicated to Anne McLaren who tragically died on the 7th of July 2007.

Affiliation The Wellcome Trust/Cancer Research UK Gurdon Institute, University of Cambridge, Cambridge, United Kingdom

Competing Interests

The authors have declared that no competing interests exist.

Author Contributions

SMCdSL, KH, TCS, WM, MAS, and AM conceived and designed the experiments. SMCdSL, KH, TCS, and WM performed the experiments, SMCdSL, KH, TCS, WM, and AM analyzed the data, and wrote the paper. MAS and AM contributed reagents/materials/analysis tools.