Eight isolates of methicillin resistance Staphylococcus aureus(MRSA) (SA40,SA32,SA30,SA13,SA10,SA36,SA3 and SA7) with different resistance phenotypes  to macrolides , lincosamides and streptogramins Were used to detect theexpression of msrA, msrB, and linA/linA’genesby using  real time polymerase chain reaction before and after treatment with antibiotics (erythromycin , clarithromycin , clindamycin and lincomycin) calibrated with triosphosphateisomerase.There highst expression of these genes was after 18 hours. It was  an induction in the expression of msrA gene in isolates (SA40,SA32,SA30 and SA13) in presence of erythromycin,however,the  isolates showed reduction in expression level of this gene .

Expression of msrB gene had been estimated  along with the using of clarithromycin and there was induction in msrB expression in isolates (SA40,SA30,SA32,SA13,SA36,SA10and SA7) while the expression level was reduced in isolate (SA3). Isolates (SA30 and SA13) showed induction of linA/linA’ expression with the using of clindamycin and lincomycin respectively.