Variation in RAPD-PCR patterns may not be attributable to genetic differences among Salmonella Enteritidis

Salmonella enterica serovar Enteritidis (SE) is a major public healthconcern because of the foodborne illness it causes in the US every year. Thesource of the most recent outbreak of SE was found to be table eggs, and eggshave been a known source for this pathogen since its emergence in the 1950s.The Centers for Disease Control and Prevention (CDC) uses PFGE to identifygenetically related Salmonella strains, but the ability of pulsed-field gelelectrophoresis (PFGE) to discriminate between epidemiologically unrelated SEisolates is limited due to their clonal nature. Random amplified polymorphic DNA(RAPD) PCR has been proposed as an alternative tool for distinguishingbetween SE isolates, but suffers from poor reproducibility. The goal of thedescribed research was to determine whether increasing the PCR stringencywould reduce the amount of randomness in SE RAPD DNA patterns.