title: RNA-Seq
design: Explanation of the extraction strategy for valid sequences (clean reads): 1. Clean Strategy: Cut off the first 3 bases; Remove the adapter that cuts the mRNA, and retain the reads with a length of more than 20. Remove the bases with a quality lower than 20, and retain the reads with a length of 20 or more. Remove the reads whose base quality is lower than 20 and account for 30% of the total. discard NN, discard polyG and polyA, retain reads with a length of more than 20; 2. End-to-end cleaning strategy: Cut off the first 3 bases; Remove the adapter that cuts the mRNA, and retain the reads with a length of more than 20. Remove the bases with a quality lower than 20, and retain the reads with a length of 20 or more. Remove the reads whose base quality is lower than 20 and account for 30% of the total. discard NN, discard polyG and polyA, retain reads with a length of more than 20;