1. Department of Pathology (R.W.E.C., M.P.B., E.A.K., P.G.T., C.J.W.), University of Cambridge, Cambridge CB2 1QP, United Kingdom;
2. Medical Research Council-Rosalind Franklin Centre for Genome Research (J.M.L., T.C.F.) Hinxton, Cambridge CB10 1SB, United Kingdom