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Note: To switch between the expanded and collapsed state, right click in the joined track label, and choose between Expand and Collapse (see Changing the Appearance of Tracks Track appearance).
Joining graphs into a single annotation track can be very useful for expression data from multiple experiments. Here, data from several experiments at different times during the development of an organism are shown together in a single track, and it is easy to see that expression of genes is being regulated over time.
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