RT Book, Section A1 Roden, Dan M. A1 Van Driest, Sara L. A2 Brunton, Laurence L. A2 Knollmann, Björn C. SR Print(0) ID 1193227183 T1 Pharmacogenetics and Pharmacogenomics T2 Goodman & Gilman's: The Pharmacological Basis of Therapeutics, 14th Edition YR 2023 FD 2023 PB McGraw-Hill Education PP New York, NY SN 9781264258079 LK accessmedicine.mhmedical.com/content.aspx?aid=1193227183 RD 2024/11/07 AB Patients vary in their responses to drug therapy. Some patients derive striking and sustained benefits from drug administration, others may display no benefit, and still others display mild, severe, or even fatal adverse drug reactions (ADRs). Common sources of such variability include noncompliance, medication errors, clinical factors, drug interactions (see Chapter 4 and Appendices I and II), and genetic factors. Pharmacogenetics is the study of the genetic basis for variation in drug response and often implies large effects of a small number of DNA variants. Pharmacogenomics, on the other hand, studies larger numbers of variants, in an individual or across a population, to explain the genetic influences on drug response. Discovering which variants or combinations of variants have functional consequences for drug effects, validating those discoveries, and ultimately applying them to patient care and to drug discovery are the tasks of modern pharmacogenetics and pharmacogenomics.