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 , and RT-Primer (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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