Polymorphism in the pertussis toxin promoter region affecting the DNA-based diagnosis of Bordetella infection

The pertussis toxin (PT) promoter region is a frequently used target for DN A-based diagnosis of pertussis and perapertussis infections. The reported p olymorphism in this region has also allowed discrimination of species in mi xtures with several Bordetella species by their specific PCR amplicon restr iction patterns. In the present study, we investigated the degree of polymo rphism in order to confirm the reliability of the assay, Five different seq uence types of the amplified 239- or 249-bp region were found among the 33 Bordetella pertussis, B. parapertussis, and B. bronchiseptica American Type Culture Collection reference strains and patient isolates analyzed. Accord ing to the sequences that were obtained and according to the PT promoter se quences already available in the databases, restriction enzyme analysis wit h TaqI, Bg/I, and HaeII, which gave four different patterns, can be perform ed to reliably identify B. pertussis, B. papapeptussis, and B. bronchisepti ca.