The subject of drug genetics (Pharmaco genetics) is the determination of genetic factors underlying individual differences in response to drugs and the use of this information for the success of treatment. In addition to other factors, genetic factors also underlie the differences in the use of drugs by individuals. In addition to the failure to obtain the desired benefit from the treatment, side effects of the drugs pose an important problem. The rate of drug side effects resulting in death is reported as approximately 3 per thousand.

Nowadays, it is widely accepted that the treatment should be planned individually, taking into account the unique nature of each patient, and the usefulness of genetic information in the planning of treatment in order to achieve success in many diseases, especially cancer.