[1] Leeds Teaching Hosp, St James Inst Oncol, Leeds, W Yorkshire, England
[2] Hosp Clin Barcelona, Hematol Dept, Barcelona, Spain
[3] St Jamess Inst Oncol, Leeds, W Yorkshire, England
[4] Alnylam Pharmaceut, Cambridge, MA USA
[5] Univ Barcelona, Hosp Clin Barcelona, Hematol Dept, Inst Hematol & Oncol, Barcelona, Spain