# Metaphlan4 Unknown taxa 70%

**URL:** <https://forum.biobakery.org/t/metaphlan4-unknown-taxa-70/7972>\
**Category:** MetaPhlAn\
**Created:** [April 2, 2025, 12:25pm UTC](https://forum.biobakery.org/t/metaphlan4-unknown-taxa-70/7972 "2025-04-02T12:25:51Z")\
**Posts on this page:** 1\
**Page:** 1

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**Author:** ![imontero](https://yyz1.discourse-cdn.com/flex027/user_avatar/forum.biobakery.org/imontero/32/3411_2.png) [@imontero](https://forum.biobakery.org/u/imontero)\
**Post date:** [April 2, 2025, 12:25pm UTC](https://forum.biobakery.org/t/metaphlan4-unknown-taxa-70/7972/1 "2025-04-02T12:25:51Z")

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Hello:

I ran my Illumina 2x150bp 10 million reads samples in Metaphlan 4.0.6 insede Biobakery workflows with mpa\_vOct22\_CHOCOPhlAnSGB\_202212 database. Then I build a phyloseq object in R and try to plot relative abundance in a ggplot with phyloseq aggregated to Species (microbiomeutilities::aggregate\_top\_taxa2) and compositional transformation (phyloseq::transform\_sample\_counts). I obtained up to 75% of Unknown relative abundance.

When I analyzed the same samples in a Metaphlan3 2 years ago I did not obtained any Unknown.

Is that Unknown percetage normal?

Thank you