1. Department of Dermatology, University of Michigan, Ann Arbor, MI 48109.
2. Department of Developmental Biology, Genentech, South San Francisco, CA 94080.
3. Department of Dermatology, Mayo Clinic, Rochester, MN 55905.
4. Department of Medicine (Gastroenterology), Vanderbilt University, Nashville, TN 37203.
5. Collagen Corporation, Palo Alto, CA 94303.