777EVALUATION OF THE GENOTOXIC EFFECT OF SALVADORA PERSICA ON MICE BONE MARROW CELLSThe miswak is a typical toothbrush made from the branches of the Salvadora persica (Salvadoraceae). In addition to consolidation the gums, it inhibits tooth decay, eliminating toothaches and break further increase in decay that has already set in. It creates a scent in the mouth, eliminates bad odor, improves the sense of taste, and causes the teeth to radiance and shine. The other portions of the tree have therapeutic values as corrective, deobstruent, liver tonic, diuretic, analgesic, anthelmintic, astringent, lithontriptic, carminative, diuretic, aphrodisiac, and stomachic. The present review is therefore an effort to give detailed survey of the lite rature on photochemistry and pharmacological activities of miswak. Genotoxicity of S. persica was evaluated on mice bone marrow cells using cytogenetics and molecular biology markers. Evaluating the chromosome aberrations (CAs), as well as measuring the mitotic index (MI) of dividing bone marrow cells, by injecting the mice with different concentration of the extract at different time intervals following the applications. The results showed significant increase in the formation of chromosome aberrations of mice bone marrow cells, in a dose and time dependent manner. Measuring the mitotic index (MI), revealed a remarkable decrease in cell division, and almost all concentrations produced a low MI, 80.40%, 73.87%, 49.93% and 36.76% at 125, 250, 500 and 1000mg /kg b.w. respectively ) when compared to the control. The study reveals that a week chromosome damaging effect even at high doses with long durations, which indicates the safety of the plant at low doses. The researchers recommend that extreme supervision must be applied upon uncontrolled using of S. persica and the high doses must not be used except when highly needed.nasseralshibly@yahoo.comResearch822017 Salvadora persica,Genotoxicity,Natural products,Chromosomal aberrations,Sister chromatid exchanges,MiceNasser Mohd Yousef AlshiblyDNasser Moh`d Yousef Alshibly