I am working with 16S gene sequences in a metagenomics study. I was wondering what --p-perc-identity in "qiime feature-classifier classify-consensus-blast" means. If I set a --p-perc-identity 0.97 value, but an ASV is only classified at phylum level, what does it mean? To consider two different sequences within the same phylum only a 0.7 percentaje identiity is needed, but if 0.97 is setted, I don't undesrtand how the taxonomical truncation is made. Is there any consensus sequence in the database at phylum level and the --p-perc-identity 0.97 is compared against that one?
I hope you can help me, thank you in advance.