Should drugs focus on race?

September 26, 2005

Many wonder whether the focus of genetically directed pharmacotherapy should be tied to race at all. According to the Nuffield Council on Bioethics, race and ethnicity cannot be given precise biological or genetic definitions because of the considerable genetic variation within population groups depending on the patient's place of birth and other variables.

The council acknowledges that genetic variation does exist among population groups, but believes that should not be taken to imply that sharp lines can be drawn on the basis of genetic information that coincides directly with racial categories. The organization also states that belonging to a particular racial group is not a substitute for a pharmacogenetic test to determine whether a genetic variant exists.

Genotyping for P-450 DNA sequence variants is already a technology available from several companies that offer testing services to physicians or to support clinical trials. But what is still in its infancy is the knowledge base relating the variants found to drug response. Once developed, the clinical applications seem almost endless, although whether insurance firms would cover the costs of the tests would depend upon how likely the pharmacogenetic data were to optimize therapy and prevent costly adverse drug reactions. Since P-450 genotyping would only have to be done once in a lifetime, and require only a drop of blood for DNA analysis, the benefits of testing patients could be lasting and worthwhile.

"It is extremely important for pharmacists to understand these principles and educate themselves about pharmacogenetics because it impacts so many patients," said Lawrence Carey, Pharm.D., assistant professor in Philadelphia University's physician assistant program. "Many times we see a drug failure and blame the drug. In reality, it may be the patient's pharmacogenetic profile that is responsible for the lack of response." But, he believes testing will be done on an as-needed basis, due to cost and privacy concerns.

Johnson, who is also a professor and chair of pharmacy practice at UF, agreed. She said that within the next few years, we'll see more use of pharmacogenetics, and she encourages pharmacists to work on their knowledge base in this area, "so as to be well poised to utilize this information in their practice."