Pharmacogenetics is the application of knowledge about a person’s genetic makeup to predict his or her response to a particular drug. Thus, in the future, physicians may be able to conduct genetic tests before prescribing a medication to determine whether the patient is likely to respond to the medication or to experience adverse side effects. To obtain this knowledge, researchers must compare large numbers of patients who do or do not respond to a medication, or who do or do not experience side effects. They must then analyze the DNA sequences of these differing populations to identify differences that predict the patients’ responses. In this way, a person’s DNA sequence profile can be used to tailor treatment to his or her specific condition, even if the actual DNA sequences that are involved in the disorder are unknown. Some scientists have argued that the discovery of DNA sequence variants relevant to pharmacogenetic issues raises fewer ethical and legal concerns than do genetic analyses that attempt to identify genes associated with a disease. This is because physicians would not test patients for
