1. Department of Genetics and Cancer Institute of New Jersey, Rutgers, The State University of New Jersey, 604 Allison Road, Piscataway, NJ 08854-8082 U.S.A.
2. Department of Pathology, University Health Network, 200 Elizabeth St., Toronto, Ontario, Canada, M5G 2C4.
3. NCIC Clinical Trials Group, Queen's University, Kingston, Ontario, Canada, K7L 3N6.