AmpliChip for Cytochrome P-450 Genotyping: The Epoch of Personalized Prescriptions

The clinical importance of genetic polymorphisms in drug metabolism is well-known in clinical pharmacotherapy. The first widely available pharmacogenomic microarray technology approved by the Food and Drug Administration as a medical device to clinically genotype genetic polymorphisms in drug metabolism is now available with the launch of AmpliChip technology. This readily accessible clinical microarray test allows the genotyping of cytochrome (CYP) P-450 2D6 and 2C19 and marks a milestone in the epoch of evidence based personalized medicine. Many commonly used drugs are substrates for CYP2D6 and CYP 2C19 and hence may potentially demonstrate phenotypic differences as poor, intermediate, extensive, and ultrarapid metabolizers. These phenotypic variations could lead to expressed differences in pharmacotherapeutic patient outcomes. AmpliChip currently allows for testing of multiple alleles (31) in a single assay. Other technologies for pharmacogenomics are on the horizon. This article reviews the importance of polymorphic enzymes and genotyping as to how genetic polymorphisms alter pharmacotherapy and the emergence of a plethora of technologies that may become routinely available for clinical pharmacogenomic testing in the near future.