# Denoising with Deblur (only forward reads?)

**URL:** <https://forum.qiime2.org/t/denoising-with-deblur-only-forward-reads/8304>\
**Category:** User Support\
**Tags:** dada2, deblur\
**Created:** [February 11, 2019, 4:35pm UTC](https://forum.qiime2.org/t/denoising-with-deblur-only-forward-reads/8304 "2019-02-11T16:35:10Z")\
**Posts on this page:** 1\
**Showing post:** 5

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**Author:** ![arwqiime](https://forum.qiime2.org/user_avatar/forum.qiime2.org/arwqiime/32/12728_2.png) [@arwqiime](https://forum.qiime2.org/u/arwqiime)\
**Post date:** [February 15, 2019, 3:26pm UTC](https://forum.qiime2.org/t/denoising-with-deblur-only-forward-reads/8304/5 "2019-02-15T15:26:08Z")

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I have tested the outcome of concatenated reads outside q2, but this did not result in taxonomic annotations that I can see with deblur and dada2 (single-end). Interstingly, both single-end analyses are very similar to the deblur paired-end analysis, that I mistakenly conducted before. It could well be that the reverse reads were droppen at one step, and the 'paired-end' data seqt were just single-end in reality. Well, intersting to see this!  
A q2 quality-control evaluate-taxonomy on the two classifications (deblur single-end vs. deblur 'paired-end') resulted in the following vizualization, where the 'reference taxonomy' was deblue single-end and the 'observed taxonomy' was deblur paired-end:  
[comp-tax-Bact1-se-pe-deblur.qza.qzv](https://cdck-file-uploads-global.s3.dualstack.us-west-2.amazonaws.com/flex002/uploads/qiime21/original/2X/2/25fd3656bb809bc95f72fd4ccd6dbcc7c1ba323a.qzv) (288.1 KB)  
I assume the two taxonomy results are very similar...

I thought I could use this great tool 'qualty-control' to compare other analyes: I used a single-end dataset and analyzed it with deblur and dada2, and then compared the two taxonomy classifcations, and I got this visualization:  
[comp-Bact1-Mi1i2-deblur-dada2.qzv](https://cdck-file-uploads-global.s3.dualstack.us-west-2.amazonaws.com/flex002/uploads/qiime21/original/2X/3/325fc0895e32a5bd428109a0a69a10904cf0132d.qzv) (255.4 KB)  
Here, I'm afraid that I this result is not true. This would indicate a perfect match, but I doubt about it.  
The evaluate-taxonomy script needs two FeatureData[Taxonomy] artifacts as input data. Is it reasonable that deblur and dada2 do indeed create such very similar taxonomy results? Of course, they should, but I would expect that this should result in 'very similar' taxonomic calssifications, but not in 'identical', right?

Thanks for you great support!

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