Figure 3.

Detection of JCV DNA sequences in human medulloblastomas. DNA from nine clinical samples was analyzed for the presence of JCV sequences by PCR using primers derived from the N terminus of T antigen (A), the C terminus of T antigen (B), and the late region of the viral genome (C). PCR products were analyzed by Southern blot analysis by using specific DNA probes as shown in Fig. 2. The nucleotide composition of the amplified DNA for each region is illustrated. Nucleotides depicting the position of PCR primers are shown in bold, and underlined nucleotides show the region detected by probes used for Southern blotting. Lane 10 represents a negative control (A, B, and C).