Because strain NW was able to colonize C57BL/6 IL-10-/- mice but did not cause severe enteritis in the initial infection and did not evolve to a higher level of pathogenicity during repeated passages, we elected to examine its genetic content more closely by comparing it to the highly pathogenic strain 11168 using an in-house full open reading frame (ORF) microarray with coverage of 95% of the C. jejuni 11168 genome [50]. The gene discussed is IL10; the disease is enteritis.