Pharmacogenomics and Medicine in Malaysia: Can Your DNA Help Guide Safer Treatment?
pro Genome
Have you ever wondered why a medicine works well for one person but causes side effects—or appears not to work—for someone else?
Several factors can influence medicine response, including age, body weight, kidney and liver function, other medicines, lifestyle and the condition being treated.
However, differences in our genes may also play a role.
This area of healthcare is known as pharmacogenomics.
What is pharmacogenomics?
Pharmacogenomics, sometimes shortened to PGx, studies how variations in a person’s genes may influence their response to certain medicines.
After entering the body, a medicine may need to be absorbed, transported, activated, broken down and eventually removed.
Genes provide instructions for producing many of the enzymes and proteins involved in these processes.
Small genetic differences may affect:
- how quickly or slowly the body processes a medicine;
- how much medicine reaches its intended target;
- whether a medicine is likely to produce the expected effect; and
- the likelihood of certain adverse effects.
Pharmacogenomics therefore gives healthcare professionals another source of information when considering a medicine or dose.
It does not replace a doctor’s or pharmacist’s clinical judgement.
A pharmacogenomic result must still be considered together with the patient’s diagnosis, age, organ function, medical history, other medicines and treatment response.
How can genes affect a medicine?
One example is clopidogrel, an antiplatelet medicine commonly used to reduce the risk of blood clots.
Clopidogrel must be activated by an enzyme called CYP2C19.
Some people carry genetic variations that reduce the activity of this enzyme. Their bodies may therefore produce less of the active form of clopidogrel, potentially reducing its antiplatelet effect in certain clinical situations.
The Clinical Pharmacogenetics Implementation Consortium, or CPIC, publishes recommendations on how existing CYP2C19 results may be used when prescribing clopidogrel.
Importantly, CPIC guidelines explain how to use an available genetic result. They do not state that every person must undergo genetic testing before receiving every medicine.
Other well-studied examples include:
- warfarin, where CYP2C9 and VKORC1 variants may contribute to differences in dose requirements;
- some statins, where certain variants may influence the risk of muscle-related adverse effects;
- tramadol and codeine, whose effects can be influenced by CYP2D6 activity;
- some antidepressants, where genetic differences may affect medicine concentrations; and
- thiopurines, where TPMT or NUDT15 variations may increase the risk of serious toxicity.
The strength of evidence is not the same for every medicine–gene combination.
Some combinations have clear clinical guidelines, while others remain areas of ongoing research.
Does pharmacogenomics improve medicine safety?
Evidence is growing that pharmacogenomics can improve outcomes when it is applied to the right patients, medicines and clinical settings.
A major example is the European PREPARE study, which evaluated a panel of 12 pharmacogenes across several countries.
Patients were tested for genetic variations. Prescribing recommendations were then provided when they received medicines affected by those genes.
The study reported fewer clinically relevant adverse drug reactions among patients with actionable results who received genotype-guided treatment.
This supports the clinical use of pharmacogenomics, but it does not mean that every DNA test will improve every treatment.
The potential benefit depends on whether:
- the relevant gene is tested accurately;
- the medicine–gene relationship is supported by sufficient evidence;
- an actionable prescribing guideline exists;
- the result is available when the treatment decision is made; and
- the result is interpreted together with other clinical information.
Pharmacogenomics may reduce some avoidable uncertainty.
It cannot guarantee that a medicine will work or that side effects will never occur.
Which countries already use pharmacogenomics?
Several countries have introduced pharmacogenomics into selected parts of healthcare.
The Netherlands
The Netherlands has been one of the leading countries in developing gene-based prescribing recommendations.
The Dutch Pharmacogenetics Working Group produces guidance to help healthcare professionals determine when a dose adjustment, additional monitoring or alternative medicine may be appropriate.
Its experience shows that pharmacogenomics is most useful when genetic results are connected to clear prescribing recommendations and integrated into pharmacy or clinical systems.
United Kingdom
The United Kingdom is progressively incorporating genomics into healthcare through the NHS Genomic Medicine Service and related professional frameworks.
Implementation remains targeted rather than universal.
Pharmacogenomic testing is used or being developed through selected clinical pathways where the evidence and healthcare infrastructure support it.
United States
The US Food and Drug Administration includes pharmacogenomic information in the labels of numerous medicines.
Depending on the medicine, this information may describe a genetic association, recommend testing or identify a biomarker that is relevant to safe use.
However, the presence of pharmacogenomic information in a medicine label does not necessarily mean routine testing is required for every patient.
These examples show that pharmacogenomics is no longer purely experimental.
However, no major country currently uses one broad genetic test to determine every medicine for every patient.
What is happening in Malaysia?
Malaysia already has genomic research capabilities, trained professionals and access to selected pharmacogenomic testing services.
However, pharmacogenomics is not yet routinely integrated into all prescribing across the Malaysian healthcare system.
One major challenge is population representation.
Much of the world’s genomic research has historically been based on populations of European ancestry.
Malaysia has a highly diverse population, including Malay, Chinese, Indian, Orang Asli and numerous indigenous communities in Sabah and Sarawak.
The frequency and clinical significance of genetic variants may differ between populations.
Malaysia therefore needs locally representative genomic data to interpret results more accurately and develop equitable precision-medicine strategies.
This is one reason the MyGenom Project is important.
What is the MyGenom Project?
MyGenom is Malaysia’s national population-genomics initiative involving the Ministry of Science, Technology and Innovation and the Ministry of Health.
The project aims to develop a Malaysian reference-genome dataset that better represents the country’s population diversity.
According to the project’s official information:
- Phase I aims to sequence 2,400 genomes from healthy Malaysians;
- Phase II aims to expand the dataset to 10,000 genomes; and
- the data are intended to support precision medicine, disease research and more locally relevant interpretation of genetic variation.
The project reported that 1,832 participants from different ethnic groups had enrolled during its 2024 recruitment period.
Its official website also states that participant recruitment is being reopened in 2026.
The government previously stated that genome sequences from the first 2,400 healthy participants were expected to become available from March 2026.
The broader Malaysian genomic database was targeted for completion by the end of 2028.
However, an announced timeline should not be treated as confirmation that the final dataset has already been completed or made available for clinical use.
Is MyGenom already being used to select medicines?
Not as a routine nationwide prescribing programme.
MyGenom is primarily building a population reference dataset and research infrastructure.
It is different from an individual pharmacogenomic test ordered to help answer a specific prescribing question.
However, its findings may eventually help Malaysia:
- identify genetic variants that are more common within local populations;
- improve the interpretation of pharmacogenomic test results;
- study medicine response among different Malaysian communities;
- determine whether international recommendations apply locally;
- support the development of Malaysian clinical guidelines; and
- build future precision-medicine and clinical decision-support systems.
MyGenom is therefore an important foundation.
Further clinical validation, professional training, data governance and healthcare-system integration will still be required before pharmacogenomics becomes part of routine prescribing.
Can pharmacogenomics eliminate medicine trial and error?
No.
Medicine response is influenced by more than genetics.
Adherence, diagnosis, kidney and liver function, medicine interactions, diet, smoking, alcohol use and other health conditions remain important.
A more scientifically accurate statement is:
Pharmacogenomics may support more informed medicine decisions and reduce avoidable uncertainty for selected medicines.
Patients should not stop, change or adjust a medicine based only on a DNA report.
Results should be interpreted by a qualified healthcare professional using recognised clinical evidence.
The future of pharmacogenomics in Malaysia
Pharmacogenomics offers a more personalised approach to understanding why people may respond differently to certain medicines.
International evidence shows that it can improve medicine safety when applied through validated testing and clear prescribing guidelines.
Malaysia’s MyGenom Project may strengthen this field by creating genomic data that are more representative of Malaysians.
The future of prescribing will not be based on DNA alone.
It will combine genetic information with medical history, laboratory findings, current medicines, lifestyle factors and professional judgement.
That is the realistic promise of pharmacogenomics: not the ability to predict every treatment outcome, but the opportunity to make some medicine decisions safer and better informed.
