Staphylococcus aureus is a dangerous human pathogen and one of the leading causes of infections worldwide While S. aureus toxin production is highly strain-specific, because most toxins of S. aureus. Some of the genetic diseases that directly associated to the lysis of the cells of the blood. One of the diseases that associated to the genetic level included the sickle cell anemia. This is particularly useful in classifying streptococcal species. A substance that causes hemolysis is a hemolysin. Different effects appeared due to more hemolysis of the cells of the blood by different microbes. β-Hemolytic streptococci are also detected in laboratory rats but rarely cause disease. Streptococcus pneumoniae and a group of oral streptococci as Streptococcus viridans or viridans streptococci display alpha hemolysis. This is sometimes called green hemolysis because of the color change in the agar. Bacteria are often divided into different families and groups. This division is based in part on the physical appearance of the bacteria as well as some of their chemical and biological characteristics. The organism does not induce hemolysis, the agar under and around the colony is unchanged, and the organism is called non-hemolytic or said to display gamma hemolysis (γ-hemolysis).