Application of RAPD-PCR for Determining the Clonality of Methicillin Resistant Staphylococcus aureus Isolated from Different Hospitals

Randomly amplified polymorphic DNA (RAPD)-PCR was applied with ten random 10-mer primers to examine the molecular diversity among methicillin resistant Staphylococcus aureus (MRSA) strains in the hospitals and to investigate the epidemiological spread of these strains between different hospitals. The main objective of the study was to identify appropriate primers, which successfully established the clonality of MRSA. Three of the primers yielded particularly discriminatory patterns and they were used to perform the RAPD analysis which revealed different bands ranging from 200 to 1500 bp. Dendogram was created by the un-weighted pair group method using arithmetic (UPGMA) average clustering and it was constructed based on the combination results of the new primers (S224, S232 and S395) which represented a novel approach for rapid screening of the strains and also provided the opportunity for monitoring the emergence and determining clonal dissemination of MRSA strains between the hospitals. Dendogram generated two main groups (Group I and II) with three clusters (A, B and C) and indicated that the strains isolated from the same hospital were closely related and they placed together in the same group. This technique could be of attractive use in controlling the sources and routes of transmission, tracking the spread of strains within hospital and between the hospitals, and especially preventing the nosocomial infections caused by the MRSA