how to make asv

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1

Hello

I am confused about the difference between asv and otu.

What I analyzed is asv or otu?

1.qiime tools import
2.qiime dada2 denoise-paired
3.qiime feature-classifier fit-classifier-naive-bayes (database)
4.qiime feature-classifier fit-classifier-naive-bayes (make taxonomy.qza)
5. qiime taxa collapse (table.qza&taxonomy.qza)

Is it correct that you created asv? What is the difference from the process of creating otu?

Thank you

2

Hi! You have an ASV data. You can think of ASV as 100% OTU, so unless you performed ASV clustering by 97% similarity to classical OTUs, you have an ASV table in your analysis. That's mean that if even 1 nucleotide different between two sequences, they will go to different ASVs. It is a main difference from OTUs. Both methods now commonly accepted, but there is a tendency that people are choosing ASVs over OTUs.

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3

Thank you for answer.

Is there a case of re-clustering after creating ASV through dada2?

I'm curious what you mean by "ASV clustering by 97% similarity to classical OTUs".

4

You can use vsearch for it vsearch — QIIME 2 2020.8.0 documentation

Sorry for bad English. If you cluster your ASV sequences by 97% similarity you will obtain OTUs.

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