[1] Dana Farber Canc Inst, Dept Pediat Oncol, Boston, MA 02115 USA
[2] Dana Farber Canc Inst, Dept Biostat Sci, Boston, MA 02115 USA
[3] Whitehead Inst, MIT Ctr Genome Res, Cambridge, MA 02142 USA
[4] St Jude Childrens Res Hosp, Dept Pathol, Memphis, TN 38105 USA
[5] St Jude Childrens Res Hosp, Dept Hematol Oncol, Memphis, TN 38105 USA
[6] Brigham & Womens Hosp, Dept Med, Boston, MA 02115 USA