1. F. P. Lindberg and E. J. Brown, Departments of Infectious Diseases and Molecular Microbiology, Washington University School of Medicine, St. Louis, MO 63110, USA.
2. D. C. Bullard, Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX 77030, USA.
3. T. E. Caver, Department of Molecular Microbiology and Immunology, University of Missouri School of Medicine, Columbia, MO 65212, USA.
4. H. D. Gresham, Research Service, Harry S. Truman Veterans Affairs Medical Center, Columbia, MO 65201, USA.
5. A. L. Beaudet, Department of Molecular and Human Genetics and Howard Hughes Medical Institute, Baylor College of Medicine, Houston, TX 77030, USA.