A set of fourteen PCR-primers was developed to aid in the identification of Fn strains derived from clinical specimens (Figure 2).71 Intriguingly, when this discriminative primer set was applied to fecal and tumor-tissue samples from CRC patients, a heterogeneous stratification of Fn subspecies was detected, with a strong enrichment of Fna in the CRC group. The gene discussed is FN1; the disease is colorectal carcinoma.