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Help Troubleshooting FASTQC

My FASTQC raised three errors. Per base sequence content, per sequence gc content, and sequence duplication levels. I read that this could be because adapters have not been trimmed. I tried using Trimmomatic to trim adapters but I'm not sure that I did it correctly. I used Illuminaclip and tried both TruSeq3 options, I also did slidingwindow averaged bewtween 4 bases with a cutoff score of 20. The sequencing lab sent me a text file of the adapters and I tried cutting and pasting it in as a custom adapter but received an additional sequence length distribution error when I ran the FASTQC. Here's the text file contents: (I removed the > symbols because they were making the post weird but they preceded each "Adapter")

Adaptor1_5p GATCGGAAGAGCACACGTCTGAACTC

Adaptor2_5p AGATCGGAAGAGCGTCGTGTAGGGAA

Adaptor3_5p TTCCCTACACGACGCTCTTCCGATCT

Adaptor4_5p GAGTTCAGACGTGTGCTCTTCCGATC

Adaptor1_3p TTCCCTACACGACGCTCTTCCGATCT

Adaptor2_3p GAGTTCAGACGTGTGCTCTTCCGATC

Adaptor3_3p GATCGGAAGAGCACACGTCTGAACTC

Adaptor4_3p AGATCGGAAGAGCGTCGTGTAGGGAA

TruSeq-Universal_Adapter_5p AATGATACGGCGACCACCGAGATCTACACTCTTTCCCTACACGACGCTCTTCCGATCT

TruSeq-Universal_Adapter_3p TCTAGCCTTCTCGCAGCACATCCCTTTCTCACATCTAGAGCCACCAGCGGCATAGTAA

Is this dual indexed?

Per base sequence content

Per sequence GC content

Sequence duplication levels

fastqc metagenomic troubleshoot

And the sequence length distribution error is due to the trimmed sequences won't have the same length as those untrimmed.

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