[1] St Jude Childrens Res Hosp, Memphis, TN 38105 USA
[2] Univ Tennessee, Coll Med, Memphis, TN 38163 USA
[3] Childrens Hosp Los Angeles, Los Angeles, CA 90027 USA
[4] Univ So Calif, Los Angeles, CA USA
[5] Inst Child Hlth, Mol Haematol Unit, London, England
[6] Hop St Louis, Serv Pediat Hematol, Paris, France
[7] Dutch Childhood Leukemia Study Grp, The Hague, Netherlands
[8] Dana Farber Canc Inst, Boston, MA 02115 USA
[9] Harvard Med Sch, Boston, MA USA
[10] Univ Milano Bicocca, Dept Pediat, Monza, Italy
[11] Osped San Gerardo, Monza, Italy
[12] Univ Hamburg, Dept Pediat Hematol & Oncol, Hamburg, Germany
[13] Hop Robert Debre, Serv Hematoimmunol, F-75019 Paris, France
[14] Hannover Med Sch, Dept Pediat Hematol Oncol, Childrens Univ Hosp, Hannover, Germany
[15] Med Coll Wisconsin, Dept Pediat, Midwest Childrens Canc Ctr, Milwaukee, WI 53226 USA