Pharmacogenomics and Personalized Medicine

With the completion of the human genome project, pharmacogenomics is regarded as part of genomic medicine and personalized medicine. While pharmacogenomics is concerned with the whole genome effect on drug metabolism and efficacy, pharmacogenetics is readily defined as the study of the genetic effect, for example, single-nucleotide polymorphism, on an individual's ability to metabolize a drug or compound. Pharmacogenomic biomarkers, in combination with other biomarkers, enable personalized medicine by identifying the right patient, with the right diagnosis/treatment, matching with the right drug, the right dose and at the right time, thus achieving clinical efficacy with no or minimized toxicity. This chapter would attempt to present pharmacogenomics, not only as an emerging, inter-dependent discipline, but as a complementing field in enhancing drug therapy. It includes the introduction, the pharmacogenomics space and the enabling drivers, the principles of pharmacogenetics/pharmacogenomics, with update on the candidate pharmacogenomics testing. Recent examples would include warfarin and irinotecan, showing that pharmacogenomic biomarkers would serve as adjuncts to other functional biomarkers for enhanced drug therapy.