1. Division of Structural Biology, Wellcome Centre for Human Genetics, University of Oxford, Oxford OX3 7BN, U.K.
2. Alzheimer’s Research UK UCL Drug Discovery Institute, University College London, Cruciform Building, Gower Street, London WC1E 6BT, U.K.
3. Centre for Medicines Discovery, University of Oxford, Oxford OX3 7DQ, U.K.