[1] Aarhus Univ, Dept Human Genet, DK-8000 Aarhus C, Denmark
[2] Aarhus Univ, Dept Med Microbiol & Immunol, DK-8000 Aarhus, Denmark
[3] Harvard Univ, Sch Med, Ctr Blood Res, Boston, MA 02115 USA
[4] Aarhus Univ Hosp, Med Res Lab, DK-8000 Aarhus C, Denmark