1. IRIS, Chiron S.p.A., Via Fiorentina 1, 53100 Siena, Italy.
2. Chiron Behring, Post Office Box 1630, D-35006 Marburg, Germany.
3. The Institute for Genomic Research, 9712 Medical Center Drive, Rockville, MD 20850, USA.
4. Institute of Molecular Medicine, Oxford University, Department of Paediatrics, John Radcliffe Hospital, Headington, Oxford OX3 9DS, UK.
5. Children's Hospital Oakland Research Institute, 5700 Martin Luther King Jr. Way, Oakland, CA 94609, USA.