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Insertion example
In the first image, the arrows show how IGB draws regions where an annotation is 'inserted'; the introns in 'non-inserted' tracks are elongated over the region of insertion.
all four gene models were selected in the main view when the sliced view was created. In the sliced view, an arrow points to an exon that is present in all four models but is larger in the first one. Introns overlapping this exon in the other three models are larger.
Deletion example
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