Precision medicine uses information about a person’s biology, environment and lifestyle to improve prevention, diagnosis or treatment. It does not mean creating a unique medicine for every patient. More often, it means identifying groups of people who are more likely to benefit from a particular test, treatment or prevention strategy.
From general evidence to more targeted care
Most healthcare still depends on evidence gathered from large groups. Precision medicine adds carefully selected information—such as biomarkers, genetic variants, tumour characteristics, laboratory results and treatment response—to help clinicians choose among evidence-based options.
The approach is already important in some areas of cancer care. Tests can identify molecular changes in a tumour that may predict whether a targeted medicine is appropriate. Pharmacogenomic testing can sometimes show how inherited genetic differences may affect the way a person processes a medicine.
What information may be used?
- Genetic information: inherited variants or changes found in a tumour.
- Biomarkers: measurable features in blood, tissue or other samples.
- Clinical information: age, symptoms, previous conditions and treatment history.
- Environment and lifestyle: exposures, diet, activity and other relevant circumstances.
- Digital measurements: carefully validated information from imaging, sensors or medical devices.
Genetic testing is not a complete answer
A genetic result usually describes probability, not certainty. Many conditions are influenced by numerous genes together with age, environment and behaviour. A variant may also have uncertain significance, meaning that evidence is not strong enough to use it for a clinical decision.
Testing can reveal information that matters to biological relatives, and results may cause anxiety or uncertainty. Pre-test information, informed consent, data protection and access to genetic counselling are therefore important.
Potential benefits
- selecting treatments more likely to help a defined group
- avoiding some ineffective treatments or preventable adverse effects
- identifying inherited risks when testing is clinically appropriate
- improving the design of clinical trials
- supporting earlier diagnosis or closer monitoring in selected situations
Limitations and risks
Precision medicine is not available or useful for every condition. Tests can be expensive, evidence may be incomplete and access may be unequal. Data collected from unrepresentative populations can make results less useful for other groups. Health systems also need strong safeguards for privacy, cybersecurity and appropriate reuse of genetic and clinical data.
A commercially purchased DNA test should not be used on its own to diagnose disease or change treatment. Clinically important findings may need confirmation in an accredited laboratory and interpretation by a qualified professional.
Questions to ask before testing
- What decision could this test change?
- How accurate and clinically useful is it?
- Could the result be uncertain or reveal unrelated information?
- Who will explain the result and the options that follow?
- How will my sample and data be stored and used?
This article provides general educational information and does not replace individual medical advice.
Sources
- US National Institutes of Health: The Promise of Precision Medicine
- NHLBI: Precision Medicine Activities
- National Human Genome Research Institute: Pharmacogenomics
Last reviewed: 28 August 2026