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The aligner indexes in the Annotation models section are required if you wish to align to a subset of the genome as defined by the annotation model, e.g. target amplicons or the transcriptome. The reference sequence is still required to generate an aligner index for an annotation model. As with whole genome alignment, indexes are aligner specific, although some aligners share indexes and are version specific (see Reference aligner indexes). The aligner indexes generated will be added to the corresponding annotation model table (Figure 2).

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