Genes tested in pharmacogenetics
Genes serve as the instructions our bodies use to develop, grow and function throughout our life. In pharmacogenetics (PGx), genes are tested for their association with predicted medication response. Genetic variations found in these genes can affect how the body responds to certain medications, influencing the medication’s effectiveness and potential side effects.
What is SLCO1B1?
SLCO1B1 is a gene that provides instructions for making the OAT1B1 transporter, which plays a key role in medication transport within the body, and is mainly found in the liver.
PGx testing of SLCO1B1
Genetic variation—the natural differences in DNA sequences between individuals—can affect how different people process the same medication. Because of specific genetic variation, the OAT1B1 transporter may work differently from person to person.
The results of SLCO1B1 PGx testing can predict how a medication is moved through and processed in the body by your child’s OAT1B1 transporters, which can help their health-care team choose or adjust their medication and dosage.
Medications affected by SLCO1B1
Currently, there is one medication class (statins) that is affected by genetic variation in SLCO1B1. If your child’s transporters are predicted to work differently than the average population, it may affect how long these medications circulate within the body:
- Statins – medications that help lower cholesterol
- Atorvastatin
- Simvastatin
- Lovastatin
- Pravastatin
- Rosuvastatin
- Fluvastatin
- Atorvastatin
The medications listed above are referred to by their generic names. You may hear your child’s medication called by a different brand name. Generic medicines and brand-name medicines share the same active ingredient and offer the same performance, safety and effectiveness. This medication list is also subject to change with increasing research on SLCO1B1.
SLCO1B1 gene function statuses
The results of a genetic test of SLCO1B1 are sorted into function statuses. There are three different function statuses for SLCO1B1:
- Poor function – the OAT1B1 transporter functions significantly less than the average population
- Your child’s health-care team may recommend starting with a lower dose of medication or switching to a different medication to ensure it works safely and effectively for your child.
- Your child’s health-care team may recommend starting with a lower dose of medication or switching to a different medication to ensure it works safely and effectively for your child.
- Decreased function – the OAT1B1 transporter functions less than the average population
- Your child’s health-care team may recommend starting with a lower dose of medication to ensure it works safely and effectively for your child.
- Your child’s health-care team may recommend starting with a lower dose of medication to ensure it works safely and effectively for your child.
- Normal function – the OAT1B1 transporter functions as expected
- Most medications should work as expected at standard doses.
- Most medications should work as expected at standard doses.
These functions are not an indicator of your child’s health—they simply predict whether your child might need a different dose of medication or a different medication entirely. In addition to PGx test results, your child’s health-care team will still consider medical history and other factors to ensure the best treatment for your child.
To learn more about how genes relate to medication use, see Genetics basics for pharmacogenetics.
Why is my child’s PGx status important?
OAT1B1 transporters can move a medication slower throughout the body, affecting how well it works. Think of these transporters as a bus system. The buses pick up passengers from the station and take them to their destination. If the buses are slow or don’t have enough seats, passengers start piling up at the station, leading to delays and congestion.
Similarly, if your child’s OAT1B1 transporter function is altered, certain medications may be processed differently, which can increase the risk of unwanted effects.