The virulence genes involved in motility (flaA), adhesion (cadF, dnaJ and racR), invasion (pldA, virB11 and ciaB), cytotoxin production (cdtA, cdtB and cdtC), lipoprotein encoding (ceuE) and GB syndrome (wlaN and cgtB) were the main genes detected in the Campylobacter spp. The gene discussed is CIAO2B; the disease is Down syndrome.