# Taxonomic Data: Using 18S-Nemabase in Qiime2 instead of Silva?

**URL:** https://forum.qiime2.org/t/taxonomic-data-using-18s-nemabase-in-qiime2-instead-of-silva/28835
**Category:** General Discussion
**Tags:** taxonomy, feature-classifier
**Created:** [January 8, 2024, 8:16pm UTC](https://forum.qiime2.org/t/taxonomic-data-using-18s-nemabase-in-qiime2-instead-of-silva/28835 "2024-01-08T20:16:13Z")
**Posts on this page:** 1
**Showing post:** 2

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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: [January 8, 2024, 11:38pm UTC](https://forum.qiime2.org/t/taxonomic-data-using-18s-nemabase-in-qiime2-instead-of-silva/28835/2 "2024-01-08T23:38:24Z")

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Hi @mkweber,

Thank you for the reference! I've not used NemaBase, but based on a quick skim of their paper it appears that NemaBase is curated to optimize nematode taxonomy assignment. I think it should serve you well.

It wouldn't hurt to compare to SILVA 138.1, you'd have to follow the [SILVA RESCRIPt tutorial](https://forum.qiime2.org/t/processing-filtering-and-evaluating-the-silva-database-and-other-reference-sequence-data-with-rescript/15494/3) yourself to see if there have been any changes, but I doubt there would be any significant changes.

You can even use GenBank data to make your own database too, and compare... for example there is [this tutorial](https://forum.qiime2.org/t/using-rescript-to-compile-sequence-databases-and-taxonomy-classifiers-from-ncbi-genbank/15947), and [this one](https://forum.qiime2.org/t/using-rescripts-extract-seq-segments-to-extract-reference-sequences-without-pcr-primer-pairs/23618) too.

Just make sure that the NemaBase, or any "specific" database you make use of, has "outgroup" taxa. That is, a collection of non-Nematode sequences within the reference database. If there are no outgroups, then quite many sequences will be classified as "Nematodes" when they are not. This is often overlooked.

But I think you'd be just fine using NemaBase. 🙂

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