# assigning taxonomy at 97 or 98% similarity
**URL:** https://forum.qiime2.org/t/assigning-taxonomy-at-97-or-98-similarity/22254
**Category:** Technical Support
**Created:** [February 21, 2022, 9:34pm UTC](https://forum.qiime2.org/t/assigning-taxonomy-at-97-or-98-similarity/22254 "2022-02-21T21:34:57Z")
**Posts on this page:** 5
**Page:** 1
### Author:  [@rosave](https://forum.qiime2.org/u/rosave)
#### Post date: [February 21, 2022, 9:34pm UTC](https://forum.qiime2.org/t/assigning-taxonomy-at-97-or-98-similarity/22254/1 "2022-02-21T21:34:57Z")
Hi,
I'm using Qiime 2021.11 version and want to assign taxonomy to some individual sequences files. I performed 16S v3/v4 sequencing through the company GENEWIZ for some bacterial isolates, and besides providing me with the raw forward and reverse reads, they also provided me with 1 consensus sequence filed (already merged and trimmed) for each sample. So starting with this sample I did the following:
qiime tools import --input-path 132\_1B.fasta --output-path venom.qza --type 'FeatureData[Sequence]'
qiime feature-classifier classify-consensus-blast --i-query venom.qza --i-reference-reads silva-138-99-seqs.qza --i-reference-taxonomy silva-138-99-tax.qza --o-classification blast-venom.qza
qiime metadata tabulate --m-input-file venom\_dada2\_taxonomy.qza --o-visualization venom\_dada2\_taxonomy.qzv
However, I believe that by assigning taxonomy this way I am doing it to 99% similarity, is that correct? If so, how could I do to do to 98 or 97% similarity?
I can get down to genera for most samples but not species and I'm wondering if I could get closer by loosening my similarity restrictions.
Thank you!
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### Author:  [@Keegan-Evans](https://forum.qiime2.org/u/Keegan-Evans)
#### Post date: [February 23, 2022, 9:34pm UTC](https://forum.qiime2.org/t/assigning-taxonomy-at-97-or-98-similarity/22254/2 "2022-02-23T21:34:37Z")
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### Author:  [@Keegan-Evans](https://forum.qiime2.org/u/Keegan-Evans)
#### Post date: [February 23, 2022, 11:06pm UTC](https://forum.qiime2.org/t/assigning-taxonomy-at-97-or-98-similarity/22254/3 "2022-02-23T23:06:00Z")
@rosave,
Unfortunately this is likely due to the limits in the resolution of V3V4 sequencing, where taxonomic annotation is often limited to the genus rather than species level. There are a few techniques that you could try to improve your results a bit though! The simplest is to simply use the `classify-sklearn` tool in feature classifier, which generally can give _slightly_ better results. [This video](https://www.youtube.com/watch?v=Z9w2VZHJMZs) rom our Youtube channel discusses the different methods in a bit more detail.
The other thing that you can do is use a weighted taxonomic classifier which has been shown to increase accuracy of taxonomic annotation. Here is the [paper](https://www.nature.com/articles/s41467-019-12669-6) and a [tutorial](https://forum.qiime2.org/t/using-q2-clawback-to-assemble-taxonomic-weights/5859) for the plugin(q2-clawback).
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### Author:  [@Keegan-Evans](https://forum.qiime2.org/u/Keegan-Evans)
#### Post date: [February 24, 2022, 6:56pm UTC](https://forum.qiime2.org/t/assigning-taxonomy-at-97-or-98-similarity/22254/4 "2022-02-24T18:56:27Z")
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### Author:  [@system](https://forum.qiime2.org/u/system)
#### Post date: [March 28, 2022, 12:56am UTC](https://forum.qiime2.org/t/assigning-taxonomy-at-97-or-98-similarity/22254/5 "2022-03-28T00:56:57Z")
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