1. C. Winkler, W. Modi, M. W. Smith, G. W. Nelson, X. Wu, M. Carrington, Science Applications International Corporation (SAIC), National Cancer Institute, Frederick, MD 21702, USA.
2. M. Dean and S. J. O'Brien, Laboratory of Genomic Diversity, National Cancer Institute, Frederick, MD 21702, USA.
3. T. Honjo and D. Yabe, Department of Medical Chemistry, Kyoto University, Kyoto, Japan.
4. K. Tashiro, Center for Molecular Biology and Genetics, Kyoto University, Kyoto, Japan.
5. S. Buchbinder and E. Vittinghoff, AIDS Office, Department of Public Health, 25 Van Ness Avenue, Suite 500, San Francisco, CA 94102, USA.