1. Department of Medicine (K.L., S.C., V.K.K.C.), University of Cambridge, Cambridge CB2 1TN, United Kingdom
2. Institute of Medicine (K.L.), University of Bergen, 5009 Bergen Norway
3. Department of Clinical Biochemistry (I.M., D.H.), Addenbrooke’s Hospital, Cambridge CB2 0QQ, United Kingdom
4. Institute of Biochemistry (H.-H.N., R.B.), Saarland University, D-66123 Saarbrucken, Germany
5. Laboratory of Molecular Biology (J.S.), Cambridge CB2 0QH, United Kingdom
6. Department of Biochemistry (A.M.W.), North Glasgow University Hospitals, Glasgow G11 6NT, United Kingdom