1 Max Planck Institute of Experimental Medicine, Department of Neurogenetics, Hermann-Rein-Str. 3, 37075 Göttingen, Germany; University Medical Center Göttingen, Institute of Neuropathology, Robert-Koch-Str. 40, 37075 Göttingen, Germany. Electronic address: stassart@em.mpg.de.
2 Max Planck Institute of Experimental Medicine, Department of Neurogenetics, Hermann-Rein-Str. 3, 37075 Göttingen, Germany.