# Can species/genus/family boundary values be modified for analysis of functional marker genes?

**URL:** https://forum.qiime2.org/t/can-species-genus-family-boundary-values-be-modified-for-analysis-of-functional-marker-genes/15808
**Category:** User Support
**Created:** [July 22, 2020, 1:54pm UTC](https://forum.qiime2.org/t/can-species-genus-family-boundary-values-be-modified-for-analysis-of-functional-marker-genes/15808 "2020-07-22T13:54:35Z")
**Posts on this page:** 1
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### Author: ![Nicholas\_Bokulich](https://forum.qiime2.org/user_avatar/forum.qiime2.org/nicholas_bokulich/32/19937_2.png) [@Nicholas\_Bokulich](https://forum.qiime2.org/u/Nicholas_Bokulich)
#### Post date: [July 22, 2020, 2:59pm UTC](https://forum.qiime2.org/t/can-species-genus-family-boundary-values-be-modified-for-analysis-of-functional-marker-genes/15808/2 "2020-07-22T14:59:14Z")

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Hi @SandraQ2,  
Indeed, this sounds like an issue with adapting the classify-consensus-vsearch classifier for the functional gene you are working with. I recommend modifying some of the parameters to see how this changes your results — this is more or less the answer to the question posed in the title of your topic. if you have a mock community or other test data to work with it would be ideal for guiding your selections.

> [@SandraQ2](#):
>
> Either my sequences are classified at the species level

Great! Probably due to the better resolution of your marker gene

> [@SandraQ2](#):
>
> or, if not, they immediately go into the “Unassigned” bin

Could be a parameter issue, e.g., see the `perc-identity` and `query-cov` parameters.

Or could be a database issue, e.g., if the species in the database do not encompass all species you are detecting.

Or it could be an issue with non-target DNA! I recommend reading some of the archival topics on this forum for more details on troubleshooting unclassified features... see [Frequent Questions and "Best of the QIIME 2 Forum"](https://forum.qiime2.org/t/frequent-questions-and-best-of-the-qiime-2-forum/13608)

Please let us know what you find!

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