European Bioinformatics Institute-European Molecular Biology Laboratory (EMBL-EBI), Cambridge, United Kingdom.|Developmental Biology Unit, European Molecular Biology Laboratory (EMBL), Heidelberg, Germany.|Developmental Biology Unit, European Molecular Biology Laboratory (EMBL), Heidelberg, Germany.|MRC Biostatistics Unit (MRC BSU), Cambridge Institute of Public Health, Cambridge, United Kingdom.|MRC Biostatistics Unit (MRC BSU), Cambridge Institute of Public Health, Cambridge, United Kingdom.|European Bioinformatics Institute-European Molecular Biology Laboratory (EMBL-EBI), Cambridge, United Kingdom.