Genetic Variation and Genetic Relationships among S. aureus Isolates from Rizgary General Hoapital by Using RAPD-PCR.

In this study the polymerase chain reaction (PCR) was used to obtain randomly amplified polymorphic DNA profiles for genetic variation and relatedness between clinical isolates of Staphylococcus aureus obtained from Rizgary General Hospital in Erbil-Kurdistan Region of Iraq. Eleven out of thirty two Operon primers (10-mer primers) showed polymorphism among the isolates tested and generating over 522 bands, approximately 114 of which were polymorphic with sizes ranging between 520 and 5148 bp. Genetic distance among the isolates ranged between 0.2446 and 0.5373. The lowest genetic distance was found between isolate causing throat infection and the isolate causing wound infection, where as the highest genetic distance was found between isolate causing urinary tract infection and the isolate causing burn infection. Genetic variation and relatedness between isolates were determined by converting RAPD data into a Jaccard similarity matrix and analysed by UPGMA computer program. The isolates were classified into two major genetic groups named as (Sa-1 and Sa-2) with four different subgroups and seven different genetic varieties. These results suggested variation of S. aureus isolates at DNA level. Moreover, they indicate possible adaptation and relationship among infection sites and genetic varieties of S. aureus. Key words: Staphylococcus aureus, Genetic variations, Genetic relationship, RAPD technique.