# Associating a representative sequence/feature ID with samples that have that sequence

**URL:** https://forum.qiime2.org/t/associating-a-representative-sequence-feature-id-with-samples-that-have-that-sequence/16147
**Category:** General Discussion
**Created:** [August 17, 2020, 6:51pm UTC](https://forum.qiime2.org/t/associating-a-representative-sequence-feature-id-with-samples-that-have-that-sequence/16147 "2020-08-17T18:51:26Z")
**Posts on this page:** 2
**Page:** 1

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### Author: ![l.brian.patrick](https://forum.qiime2.org/letter_avatar_proxy/v4/letter/l/2acd7d/32.png) [@l.brian.patrick](https://forum.qiime2.org/u/l.brian.patrick)
#### Post date: [August 17, 2020, 6:51pm UTC](https://forum.qiime2.org/t/associating-a-representative-sequence-feature-id-with-samples-that-have-that-sequence/16147/1 "2020-08-17T18:51:26Z")

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Hello!

Two questions, actually:

1. When I get representative sequences/feature IDs after doing a vsearch, is there a way to associate a resulting sequence with the sample or samples associated with that sequence? For example, I have a feature ID that comes back as Wolbachia-- can I then determine exactly which of my samples have that sequence of Wolbachia in them?

2. Assuming that I can accomplish #1 above, is there a way to quantify how many reads within a sample are associated with the sequence?

Thank you for your time!

Best regards, Brian

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### Author: ![jwdebelius](https://forum.qiime2.org/user_avatar/forum.qiime2.org/jwdebelius/32/9655_2.png) [@jwdebelius](https://forum.qiime2.org/u/jwdebelius)
#### Post date: [August 17, 2020, 8:57pm UTC](https://forum.qiime2.org/t/associating-a-representative-sequence-feature-id-with-samples-that-have-that-sequence/16147/2 "2020-08-17T20:57:34Z")

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Hi @l.brian.patrick,

Yes!

You should have a feature id (let's use 🐕 because it's as easy as anything else). This feature ID should appear in your taxonomy artifact:

| Feature ID | Taxonomy |
| --- | --- |
| 🐕 | k\_\_Bacteria; p\_\_Proteobacteria; ... |

It will also appear in your representative sequences:

| Feature ID | Sequence |
| --- | --- |
| 🐕 | CATCATCAT |

And, in your feature table (lets name our samples 👩‍🎨, 👩‍🚀, 👩‍💻)

| Feature ID | 👩‍🎨 | 👩‍🚀 | 👩‍💻 |
| --- | --- | --- | --- |
| 🐕 0 | 1 | 100 | |

You may want to look into the [filtering tutorials](https://docs.qiime2.org/2020.6/tutorials/filtering/) specifically to see how to extract the features you want.

Best,  
Justine