for examining predicted viral miRNA hairpins based on the previously published pipeline. To make this tool more user-friendly, we also included the target gene search function. Many functionally related miRNAs cluster together to facilitate their expression and functional regulation. For example, about half of the miRNAs identiﬁed in Drosophila are reported to exhibit this clustering phenomenon; they are initially co-transcribed from one polycistronic transcript and further processed into distinct individual mature miRNAs (1,22,23). This phenomenon has been reported in EBV (11) and also was observed in our present results. As illustrated in Figure 3, two predicted candidate hairpins from this study are clustered in the transcript of BART together with several known EBV pre-miRNAs (11). 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