[1] Erasmus MC, Dept Internal Med, Rotterdam, Netherlands
[2] Erasmus MC, Dept Epidemiol, Rotterdam, Netherlands
[3] NGI NCHA, Rotterdam, Netherlands
[4] Kings Coll London, Dept Twin Res & Genet Epidemiol, London WC2R 2LS, England
[5] Wellcome Trust Sanger Inst, Hinxton, England
[6] Ctr Diagnost Eindhoven, Res Unit, Eindhoven, Netherlands
[7] Tilburg Univ, Dept Clin & Hlth Psychol, NL-5000 LE Tilburg, Netherlands
[8] Vrije Univ Amsterdam, Med Ctr, Endocrine Sect, Dept Internal Med, Amsterdam, Netherlands
[9] Univ Med Ctr Utrecht, Julius Ctr Hlth Sci & Primary Care, Utrecht, Netherlands
[10] Erasmus MC, Dept Obstet & Gynaecol, Rotterdam, Netherlands