PSMB9 and neoplasm: For ease of presentation these patterns are designated Latencies I (EBNA1 only), II (EBNA1, LMP1 and LMP2) or III (full latent gene expression), though it should be remembered that this classification is not always hard and fast; in particular, tumours expressing EBNA1 and low levels of LMP2 blur the boundary between Latencies I and II, while different tumour types designated Latency II can differ significantly in LMP1 and/or LMP2 protein levels (see table 1 footnote for further qualification).