RNA input amounts lower than 100 ng (for total RNA or enriched small RNA) require protocol adjustments. These adjustments include dilution of the 3' Adapter (A3), 5' Adapter (A5) and Reverse Transcription Primer (RTP) and adjusted endpoint PCR cycle numbers (see Appendix B of the User Guide).
The minimum amount of total RNA input depends on the small RNA content of the sample in question.
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