However, using the Fna clade-specific amplicon sequence variants to resolve Fn to a higher taxonomic resolution that includes Fna C1, Fna C2 and non-Fna subspecies of Fn, we demonstrate that only Fna C2 is significantly enriched in tumour compared to paired normal tissue (Fig. 5a, and Supplementary Tables 8 and 19; t-test, paired, P = 0.0093). Here, FN1 is linked to neoplasm.