What is Pharmacogenomics?
Pharmacogenomics is a field of medicine that investigates how a person's genetic makeup may affect how their body processes certain medications[1]. In some cases, your DNA can affect whether you have a bad reaction to a drug or whether a drug helps you or has no effect. Pharmacogenomics can improve your health by helping you know ahead of time whether a drug is likely to benefit you and be safe for you to take[2].
The United States Center for Disease Control (CDC) has a very useful primer article on the subject, including some excellent graphics for those new to the subject. As they describe, drugs interact with your body in many ways, depending both on how you take the drug and where the drug acts in your body. After you take a drug, your body needs to break it down and get it to the intended area. Your DNA can affect multiple steps in this process to influence how you respond to the drug. Let's take a look at some of their examples below. A direct link to their page is given in citations at the base of this page.
Drug Receptors
For example, some drugs need to attach to proteins on the surface of cells, called receptors, in order to work properly. Your DNA determines what type of receptors you have, and how many, which can affect your response to the drug. You might need a higher or lower amount of the drug than most people, or you might need a different drug.
(Image courtesy of CDC)
Drug Uptake
Some drugs need to be actively taken into the tissues and cells in which they act. Your DNA can affect uptake of certain drugs. Decreased uptake can mean that the drug does not work as well and can cause it to build up in other parts of your body, which can cause problems. Your DNA can also affect how quickly some drugs are removed from the cells in which they act. If drugs are removed from the cells too quickly, they might not have time to act.
(Image courtesy of CDC)
(Image courtesy of CDC)
Drug Breakdown
Your DNA can affect how quickly your body breaks down a drug. If you break the drug down more quickly than most people, your body gets rid of the drug faster and you might need more of the drug or a different drug. If your body breaks the drug down more slowly, you might need less of the drug.
(Image courtesy of CDC)
(Image courtesy of CDC)
Positive Impact of Pharmacogenomics?
A recent multi-stakeholder workshop on pharmacogenomics hosted by the European Medicines Agencyhe first session highlighted the importance of pharmacogenomics for public health[3]. Adverse drug reactions (ADRs) are an important cause of hospitalisations and deaths worldwide and contribute to higher healthcare costs. Furthermore, the risk of ADRs can increase with polypharmacy, which is associated with the aging global population. Pre-emptive pharmacogenomic testing (genotyping performed before medicine prescribing) can identify actionable genetic variants, prevent undesired ADRs, and have an impact on healthcare-associated costs. The EU-funded PREPARE study[4], an open-label trial, implemented a 12-gene panel that showed a ~30% reduction in risk of ADRs in both actionable and non-actionable genes.
Citations
- Pharmacogenomics, Cleveland Clinic, accessed 01 April 2025
- Center for Disease Control, Genomics and Your Health, Pharmacogenomics, accessed 01 April 2025
- Multi-stakeholder workshop on Pharmacogenomics 24 September 2024 Hybrid meeting / EMA, Amsterdam
- Swen et al, A 12-gene pharmacogenetic panel to prevent adverse drug reactions: an open-label, multicentre, controlled, cluster-randomised crossover implementation study, The Lancet, Volume 401, Issue 10374, 2023