[1] Univ Helsinki, Dept Med Genet, Biomedicum Helsinki, FIN-00014 Helsinki, Finland
[2] Univ Helsinki, Cent Hosp, Biomedicum Helsinki, Helsinki, Finland
[3] Inst Biomed, Mol Canc Biol Program, Helsinki, Finland
[4] Erasmus MC, Dept Internal Med, Lab Vasc & Metab Dis, Rotterdam, Netherlands
[5] Univ Dusseldorf, Univ Klinikum, D-4000 Dusseldorf, Germany
[6] Imperial Canc Res Fund, Mol & Populat Genet Lab, London WC2A 3PX, England