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Read lengths >100bp can also be used. However, it is important to note that per base sequencing quality will typically decrease as read - length increases, as more inserts will be fully covered and start to read into the poly(A) stretch and adapter sequences.
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For sequencing depth, we recommend 1-5M 5 M reads/sample. If you are mainly interested in highly expressed genes, a lower coverage can be considered whereas for lowly expressed genes, higher sequencing depth would be required.
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