# Getting representative OTU sequences

**URL:** <https://forum.mothur.org/t/getting-representative-otu-sequences/22311>\
**Category:** Commands in mothur\
**Created:** [March 17, 2025, 6:30pm UTC](https://forum.mothur.org/t/getting-representative-otu-sequences/22311 "2025-03-17T18:30:52Z")\
**Posts on this page:** 3\
**Page:** 1

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**Author:** ![ritikadev](https://yyz2.discourse-cdn.com/flex036/user_avatar/forum.mothur.org/ritikadev/32/486_2.png) [@ritikadev](https://forum.mothur.org/u/ritikadev)\
**Post date:** [March 17, 2025, 6:30pm UTC](https://forum.mothur.org/t/getting-representative-otu-sequences/22311/1 "2025-03-17T18:30:52Z")

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Hi! I am working with a big data set with over 500 samples, and I used the Mothur MiSeq SOP. I am looking to find representative OTU sequences for only around 20 OTUs. Running get.oturep() using my final.dist file will require a LOT of RAM and will take forever and a half.  
**Is there a way to get representative OTU sequences for only a select few OTUs?**  
For context, I am focusing on correlations between bacteria involving one genus of interest.

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**Author:** ![pschloss](https://yyz2.discourse-cdn.com/flex036/user_avatar/forum.mothur.org/pschloss/32/4_2.png) [@pschloss](https://forum.mothur.org/u/pschloss)\
**Post date:** [March 18, 2025, 1:17pm UTC](https://forum.mothur.org/t/getting-representative-otu-sequences/22311/2 "2025-03-18T13:17:18Z")

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Hi there - you might try using the [`method=abundance` argument](https://mothur.org/wiki/get.oturep/#method). This will pick the most abundant sequence in the OTU as the representative sequence. We find that this often gives decent results and is far less memory intensive than the distance-based approach.

Pat

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**Author:** ![system](https://yyz2.discourse-cdn.com/flex036/user_avatar/forum.mothur.org/system/32/2_2.png) [@system](https://forum.mothur.org/u/system)\
**Post date:** [March 28, 2025, 1:17pm UTC](https://forum.mothur.org/t/getting-representative-otu-sequences/22311/3 "2025-03-28T13:17:24Z")

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Closed on March 28, 2025, 1:17pm UTC

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