[1] Univ Gothenburg, Sahlgrenska Acad, Dept Clin Neurosci, Unit Neurochem, Gothenburg, Sweden
[2] Univ Gothenburg, Sahlgrenska Acad, Dept Clin Chem & Transfus Med, Gothenburg, Sweden
[3] Karolinska Inst, Ctr Genom & Bioinformat, Stockholm, Sweden
[4] Malmo Univ Hosp, Dept Clin Neurosci, Neuropsychiat Clin, Malmo, Sweden
[5] Huddinge Univ Hosp, Karolinska Inst, Dept Clin Neurosci & Family Med, Geriatr Med Sect, Stockholm, Sweden
[6] Brigham & Womens Hosp, Ctr Neurol Dis, Boston, MA 02115 USA
[7] Harvard Univ, Sch Med, Boston, MA USA
[8] Univ Munich, Dept Psychiat, D-8000 Munich, Germany