1. CRBM, CNRS UPR‐1086, IFR 24 34293 Montpellier France
2. Dana‐Farber Cancer Institute and Department of Genetics, Harvard Medical School Boston MA 02115 USA
3. Laboratoire LSR‐IMAG 38041 Grenoble France
4. Genome Therapeutics Corporation Waltham MA 02453 USA
5. National Center for Biotechnology Information, National Library of Medicine, National Institutes of Health Bethesda MD 20894 USA