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RNAseq fastqc report some failures, how to solve it?

I used fastqc to deal with my small RNA seq data, and according to the report I have some failures, do not know how to solve these situation. I post all the failure picture here, how someone can help me out? Thanks in advance.

adaptor content sequence duplicated! GC content per tile quality per base quality

rna-seq

There are no actual failures with FastQC. The red X's mean that your data falls outside the bounds of intervals (which can be changed) which are mainly for genomic DNA sequencing. Small RNA seq data is expected to have ~25 bp of actual sequence and may contain adapter sequence (which will need to be trimmed out).

Use these directions to post images: How to add images to a Biostars post Once we see the images we can assist further.

You can see that you need to trim your reads to remove Illumina small RNA adapter. This can be done by many tools. bbduk.sh from BBMap suite, cutadapt, trimmomatic and fastp.

1 answer

Adapter content might be a problem you can fix, but you should start by googling how to trim adapters, not wait around here for someone to spoon-feed you how to trim adapters.

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