Northern blot analysis of total RNA from different human brain tissues: lanes 1 and 10, normal cerebrum; 2 and 11, normal cerebellum; 3-7 and 12-17, eleven different capillary hemangioblastomas; 8, 9, 18, and 19, four different glioblastomas. The membranes were hybridized with ³²P-labeled human Epo cDNA and partially reprobed with human VEGF and VHL probes. Hybridization with β-actin served as a loading control (ND, not determined).