Molecular biology is a part of biology; based on physiology, genetic and biochemical. Molecular biology studies about the shape, structure, and function of macromolecules that have important roles in the life, such as nucleic acids, proteins…. Molecular biology techniques are very diverse and also applied in many different fields, such as molecular diagnostics (PCR, molecular hybridization); production of active substances detecting or treating diseases (producing monoclonal antibodies, making proteins with biological activity ...); gene therapy (recombinant ...). The molecular biology applications which the earliest and most visible are the medical fields. Based on genetic engineering, medicine not only relies on clinical symptoms but also impacts to directly the true reason that cause the disease: genetic abnormalities. Molecular biology pervate almost the medicine field; inside, the most potents are diagnostic and preventive