Pharmacogenetics and personalized medicine

Abstract Pharmacogenetics is the study of the genetic variation between individuals that affects their response to drugs, both therapeutically and in terms of side effects. Pharmacogenetics has been widely recognized as a fundamental step toward “personalized medicine,” also known as “precision medicine.” Guidelines for nomenclature to standardize the way pharmacogenetic variants must be reported are extensively reviewed in this chapter. The pros and cons of the available technologies used for pharmacogenetic testing and the barriers for implementation of pharmacogenetic testing in the clinic are also discussed. Several initiatives for the implementation of pharmacogenetics in the clinic have been launched and evaluations of cost-effectiveness of preemptive strategies are reviewed. Finally, examples are given of pharmacogenetics in clinical practice, and the development and integration of other fields such as transcriptomics, epigenomics, metabolomics, and microbiota research for understanding the heterogeneity of treatment outcomes is discussed.