1. Department of Biochemistry, Molecular Biology and Biophysics, Institute for Molecular Virology, Beckman Center for Genome Engineering, Comparative and Molecular Biology Graduate Program, University of Minnesota, Minneapolis, Minnesota 55455
2. Institute for Experimental Pathology, University of Iceland, Keldur v/ Vesturlandsveg, 112 Reykjavík, Iceland
3. Unité de Génétique Viral et Biosécurité, AFSSA—LERAPP, BP 53, 22440 Ploufragan, France
4. Core Research Laboratory, Instituto Toscano Tumori, Villa delle Rose, 50139 Firenze, Italy
5. HIV Drug Resistance Program, National Cancer Institute at Frederick, Center for Cancer Research, Frederick, Maryland 21702
6. Fred Hutchinson Cancer Research Center, Seattle, Washington 98109
7. Gladstone Institute of Virology and Immunology, University of California at San Francisco, San Francisco, California 94158
8. Department of Microbiology, New York University School of Medicine, New York, New York 10016
9. Division of Genome Modifications and Carcinogenesis, Research Program Infection and Cancer, German Cancer Research Centre, 69120 Heidelberg, Germany
10. Department of Infectious Diseases, King's College London School of Medicine, Guy's Hospital, London Bridge, London SE1 9RT, England
11. Department of Gastroenterology, Hepatology and Infectiology, Heinrich-Heine-University, 40225 Düsseldorf, Germany
12. Laboratory of Genomic Diversity, National Cancer Institute at Frederick, Frederick, Maryland 21701-1201
13. Viral Biochemistry Section, National Institute of Allergy and Infectious Diseases, NIH, Bethesda, Maryland 20892
14. Molecular Retrovirology Unit, Institut Pasteur, 75015 Paris, France
15. Department of Molecular Microbiology and Immunology, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland 21205