Southern blot hybridization of the 1,200-bp PCR products of Helicobacter-specific primers hybridized with helicobacter 16S rRNA gene PCR product. Lanes 1 to 13, DNA extracted from stomach tissue of six dolphins (animals 1 to 6, accession numbers 99-5656 to 99-5668); lane 14, Helicobacter positive control; lane 15, reagent control.