General PGx Questions

Pharmacogenomic (PGx) testing looks at how your genes affect your response to certain medications. Genes are pieces of DNA that provide instructions to make our bodies look and work as they do. We all have different genes. Some genes affect the way medications are processed by the body. These differences can affect how people respond to medications.

Pharmacogenetic testing can assist your healthcare provider to select and dose medications that are the best match for you, while estimating your risk for serious side effects.

We test 16 genes related to medication response and side effects. They include: CYP2B6, CYP2C, CYP2C19, CYP2C9, CYP2D6, CYP3A4, CYP3A5, CYP4F2, DYPD, HLA-A, HLA-B, NUDT15, TPMT, UGT1A1, VKORC1.

We test genes for which genotype-based prescribing recommendations are currently available from recognized professional organizations and regulatory bodies, such as the Clinical Pharmacogenetics Implementation Consortium (CPIC), the Dutch Pharmacogenetics Working Group (DPWG), and the U.S. Food and Drug Administration (FDA). These genes are primarily those related to pharmacokinetics (PK). PK genes affect what a medication does to an individual’s body. PK genes control how much of the medication is absorbed, broken down, and eventually removed from the body. It can also help determine how much of the medication is in an individual’s bloodstream. Understanding this helps researchers and healthcare professionals translate the information into clinical dosing recommendations. In addition, pharmacodynamic (PD) genes can also influence how the body responds to the medication. However, we do not test PD genes for medications relevant to psychiatry, as currently there are no genotype-based guidelines are available for these genes.

There are a few limitations to pharmacogenetic testing. These include:

·       Testing only looks at common gene differences. Rare gene differences that may account for the way you react to medications are not tested.

·       Several factors may influence the way you react to medications. Things like your age, weight, other medications and other medical conditions. Your healthcare provider will need to consider these factors along with your test results to advise on the best course of action.

·       It can take several weeks to get testing results, which could delay the initiation of treatment if your doctor is waiting for the results.

All our medication dosing recommendations come from (1) The Clinical Pharmacogenetic Implementation Consortium (CPIC), (2) The Dutch Pharmacogenetics Working Group (DPWG) and (3) The Food and Drug Administration (FDA).

Most of our studies have a turnaround time to receive pharmacogenetic results within 10-14 business days, except for the PGx-STaR study. Since PGx does not currently support recommendations for stimulant based medications, the pharmacogenetic report will be delivered along with the gift card at the end of the study (i.e., week 4).

Due to funding agreements and our ethics protocols, only youth and emerging adults between the ages of 6-24 are eligible to participate.

Your pharmacogenetic test results are based on your unique genetic code. Thus, each member of your family would require individual testing to determine their unique genetic code. Your results cannot be used to guide medication selection or dosing of your family members.

No. PGx testing can inform the selection and dosing of some medications, not all. Specialized areas of healthcare that PGx testing may provide benefit include:

• Autoimmune disorders (immunology)

• Blood clotting disorders (hematology)

• Cancer treatment (oncology)

• Digestive health (gastroenterology)

• Heart care (cardiology)

• Infectious diseases

• Mental health (psychiatry)

• Neurologic disorders (neurology)

• Pain management

While both involve similar pathways of processing (breaking down) food or medication, they use different mechanisms (enzymes) to do so.

Enzymes that break down food in the body, convert food into nutrients and energy that are needed to survive. Enzymes that break down medications in the body make sure the medication is absorbed, used and then removed from the body properly.

If your body metabolizes food faster or slower than normal, it does not mean you will metabolize medication in the same way.