5746 Nucleic Acids Research, 2007, Vol. 35, No. 17 ACKNOWLEDGEMENTS This work was supported by NCI Grant R01 CA113371- 01 to D.K.O., while R.G.L. and E.B. were supported by the UK Medical Research Council. The authors would like to thank Joanna Groden, Ken Marians, Steven Matson, Vilhelm Bohr, Judy Campisi and M.D. Gray for providing important reagents and Deanna Edwards for critical reading of the manuscript. Funding to pay the Open Access publication charges for this article was provided by the Graduate Center for Toxicology, University of Kentucky College of Medicine. Conﬂict of interest statement. None declared. REFERENCES 1. Goto,M. (1997) Hierarchical deterioration of body systems in Werner’s syndrome: implications for normal ageing. Mech. Ageing Dev., 98, 239–254. 2. Martin,G.M. and Oshima,J. (2000) Lessons from human progeroid syndromes. Nature, 408, 263–266. 3. Yu,C.E., Oshima,J., Fu,Y.H., Wijsman,E.M., Hisama,F., Alisch,R., Matthews,S., Nakura,J., Miki,T. et al. 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