CP and neoplasm: We examined Cp transcription in a pair of EBV-positive Burkitt's lymphoma (BL) clonal cell-lines that either maintain the original EBNA 1-only (Latency I) BL tumour phenotype (Mutu I) or have drifted in culture to express the full panel of latent antigens including EBNA 2 (Mutu III) [37].