The Science
What is Pharmacogenetics?
The science of how your genetic makeup shapes your response to medications, and how testing can guide your physician to the right drug at the right dose.
Pharmacogenetics is a field of scientific research that studies how an individual's genetic makeup affects how they will respond to medications. Its objective is to select the most optimal medication for an individual's condition at the most optimal dose. Pharmacogenetics aims to tailor medical care and maximize the quality of care.
What pharmacogenetic testing provides
Drug recommendations enabling physicians to prescribe the right dose of the right drug from the start
Identification of medications compatible with your genetic profile to avoid drug-related toxicity
Recognition of medications most effective in treating your current medical condition
Pillar 1
Pharmacokinetics
What the body does with a medication
Pharmacokinetics describes the journey a drug takes through the body: absorption, distribution, metabolism, and excretion.
Absorption
How the medication enters the bloodstream: through the gut, lungs, skin, or injection.
Distribution
How the drug travels to the tissues and organs where it's needed.
Metabolism
How liver enzymes break down or activate the drug. This is where genetic variation matters most.
Excretion
How the body clears the drug, primarily through the kidneys, sometimes via bile, sweat, or breast milk.
The primary implication of pharmacogenetics within pharmacokinetics is in the metabolism stage. Many drugs undergo biotransformation into their active form via liver enzymes, and many medications are also cleared from the body via those same enzymes. Antidepressants are a familiar example.
Pharmacogenetic testing of liver-enzyme function helps determine whether a given individual is able to activate a medication within their system, and at what speed they clear it. Variations in clearance determine whether a dose reduction or dose increase is needed to achieve optimal response, and to mitigate side-effect risk.
Backed by high-level evidence
The majority of metabolism information has been validated by multiple studies and is considered high-level evidence, much of it FDA-approved. FDA drug labels are used to determine dosing recommendations.
Pillar 2
Pharmacodynamics
What a medication does to the body
Pharmacodynamics is the study of how drugs affect their target sites in the body. It determines whether a medication's mechanism of action is compatible with a given receptor, and whether it can perform its function: inhibition, agonism, sensitization, or desensitization.
Genetic variants determine the way proteins work together to shape both our appearance and our function. Inter-individual variation in receptor function is prevalent, which is why different people respond differently to the same medication.
Pharmacodynamics can offer a glimpse of baseline function. But there are countless mechanisms by which a medication works, and the body has countless compensatory pathways. That is why testing only one target gene against one medication tends to be insufficient, and why a polygenic approach is essential.
An evolving evidence base
Pharmacodynamic genes comprise both high-level and lower-level evidence, as studies continue to replicate and validate findings.
The Polygenic Approach
A polygenic approach is an algorithm that tests and weighs the impact of many variants on response to a given medication. Each gene receives a different weighting and score based on its level of involvement in medication response. The percentage by which a full score is met determines the degree of response to a given medication, or the degree of risk for a given vulnerability.
Built on Clinical Standards
Our pharmacogenomic recommendations are guided by the Clinical Pharmacogenetic Implementation Consortium (CPIC), overseen by Stanford University and the College of American Physicians (CAP).
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Go Deeper Into the Science
Discover how second-generation pharmacogenetics goes beyond traditional testing, or see exactly how your sample becomes a personalized recommendation.