# Removing Primers: Cutadapt vs Denoising

**URL:** https://forum.qiime2.org/t/removing-primers-cutadapt-vs-denoising/20376
**Category:** General Discussion
**Tags:** dada2, primers, cutadapt
**Created:** [August 3, 2021, 4:48pm UTC](https://forum.qiime2.org/t/removing-primers-cutadapt-vs-denoising/20376 "2021-08-03T16:48:15Z")
**Posts on this page:** 1
**Showing post:** 4

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### Author: ![SoilRotifer](https://forum.qiime2.org/user_avatar/forum.qiime2.org/soilrotifer/32/21071_2.png) [@SoilRotifer](https://forum.qiime2.org/u/SoilRotifer)
#### Post date: [August 3, 2021, 8:24pm UTC](https://forum.qiime2.org/t/removing-primers-cutadapt-vs-denoising/20376/4 "2021-08-03T20:24:47Z")

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> [@elsamdea](#):
>
> Thank you so much for responding so quickly and in such detail! The truth is that it is great to have a forum where you can expose your doubts and receive such complete answers. My congratulations to the moderators! 👏 👏 👏

Thank you for the high praise! We do try our best. 🙂

> [@elsamdea](#):
>
> In these two cases, the `--discard-untrimmed` wouldn't work because the filtering was too restrictive or too lax, right? Or I am wrong?

Correct, often low-quality data will make some of these parameters too restrictive. Especially, if you are using the incorrect primer sequence(s) and/or orientation, as outlined [in this thread](https://forum.qiime2.org/t/q2-cutadapt-output/17031/24). This is also why I also append the following commands (often only the first one is required, but I use both just because):

```auto
--p-match-adapter-wildcards \
--p-match-read-wildcards \

```

> [@elsamdea](#):
>
> Again, thank you so much again for your help!!

You're welcome!  
-Mike

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