[1] European Bioinformat Inst, European Mol Biol Lab, Wellcome Genome Campus, Cambridge CB10 1SD, England
[2] St Vincents Inst Med Res, 41 Victoria Parade, Fitzroy, Vic 3065, Australia
[3] Canc Res UK Cambridge Inst, Cambridge, England
[4] Wellcome Trust Res Labs, Sanger Inst, Wellcome Genome Campus, Cambridge, England
[5] European Mol Biol Lab, Genome Biol Unit, Meyerhofstr 1, D-69117 Heidelberg, Germany
[6] Helmholtz Zentrum Munchen, German Res Ctr Environm Hlth, Inst Computat Biol, Neuherberg, Germany