Principles of Pharmacogenomics

Response to drug therapy varies considerably among individuals. Variations in genes involved in drug disposition and in eliciting drug response significantly contribute to the interpatient variability in drug response. Pharmacogenomics involves the search for genetic variations influencing drug response and offers the opportunity to improve drug effectiveness and safety through a personalized approach to drug prescribing. In addition to potentially improving the use of existing therapies, pharmacogenetics has led to the development of novel drugs based on an improved understanding of genetic contributions to disease pathophysiology. This chapter provides an overview of variation in the human genome and how this variation influences drug pharmacokinetics and pharmacodynamics, thus affecting drug response.