Bibliographical noteFunding Information:
We apologize to those authors whose work could not be included here due to the constraints of space. We would also like to thank Sam Donohoe and Michael Wright for their assistance with the manuscript. TJG was funded by an NIH Postdoctoral Genome Training Grant fellowship. This work was also supported by grants from the National (USA) Cancer Institute (1R33CA84698) and from the NIH (RO1 AI41109-01).