Summary of sample information including high-quality read counts, taxonomic assignment of most abundant genus in each sample, and level of human contamination.

The clinical labels represent: ‘healthy’ – healthy periodontal pocket; ‘early’ – early periodontal disease (bleeding under probing but no attachment loss), ‘moderate’ – moderate periodontal disease; ‘advanced’ – advanced periodontal disease. For a description of the clinical parameters used to make these determinations see Materials and Methods. The absence of metagenomic data from subject 5 is indicated with ‘NA’ in the appropriate cells.