Understanding Pharmacogenetics and the Benefits of DNA Tests for Medication

Written by: 
Jeanne Conradie

In order to understand the benefits of DNA tests for prescribing medication, such as GENE-Rx™, we first need to understand the complexities of pharmacogenetics and what this can reveal about our genetics and how our genes affect our respondence to particular drugs and medication. The fact that we can predict an individual’s response to medication based on their genetics has been around for just over 100 years, but people are only now realising its seemingly endless potential.

What is pharmacogenetics?

Pharmacogenetics is a branch of both genetic testing and pharmacology which deals with the influence an individual’s genetic makeup will have on a certain drug and vice versa. Pharmacogenetics generally refers to how a single gene variation influences the body’s response to a particular drug. Pharmacogenomics is used as a broader term for the study of genes (more specifically genome) and how genes can influence the body’s response to a particular drug or medication. These terms are often used interchangeably but the bottom line is that this research has the potential to completely change the way medication is prescribed.

This information would be especially beneficial in helping treat and cure serious illnesses in individuals diagnosed with cancer, autoimmune diseases, highly infectious and drug resistant diseases like Tuberculosis.

In Allen D. Roses’ Pharmacogenetics and the practice of medicine he writes, “The ability to rapidly profile patients who are likely to benefit from a particular medicine will also streamline drug development and provide opportunities to develop discrete medicines concurrently for different patients with similar disease phenotypes.” In a nutshell what he means is that the more this study is implemented in genetic testing the more streamlined the process of treating patients with the right medication will become streamlined.

Genome Wide associated studies have enabled us to identify specific SNPs that are involved with the metabolism and transport of drugs in our body – basically genes that are involved in the pharmacokinetics and pharmacodynamics of the drug.

Why is Knowing Your Potential for Metabolising Medication is Important

When your body is unable to metabolise a drug the way it was intended it can result in a reaction known as acute toxicity. Errors in drug administration or prescription pose a great risk to patients and it is quite common.  Hospital admissions for patients suffering from drug toxicity are frequent and this is incredibly dangerous. Reacting to taking a drug over a short period of time (usually in the span of 24 hours) or even after just one dosage can be fatal.

To negate the effects of acute toxicity hospital staff will either administer activated charcoal or pump the patient’s stomach. A DNA test for medication can prevent this from happening. The biggest drug that cause drug toxicity in South Africa in recent history is Warfarin.

Warfarin is used to treat thrombosis and is a popular treatment in the form of oral anticoagulant therapy. Because its safe use is dependent on the variable toxic dosage a DNA test for medication would be essential before deciding to use it.

GENE-Rx™: What is a DNA Test for Medication?

A DNA test for medication like the GENE-Rx™ is designed to look at certain genes (61 single nucleotide polymorphisms) involved with the pharmacokinetics and pharmcodynamics of certain drugs, to better understand how individuals will respond to the prescribed medication and whether they are likely to suffer from any adverse side effects of the prescribed medication. This also has to do with how different people’s DNA metabolises different substances in differing ways.

An example of this from a study done by the American College of Medical Genetics and Genomics called Laboratory testing of CYP2D6 alleles in relation to tamoxifen therapy found that the long standing treatment for breast cancer, tamoxifen, was found to be less effective in those who have lower CYP2D6 enzyme activity.  – CYP2D6 is responsible for converting Tamoxifen to its active form Endoxifen. Individuals with lower CYP2D6 enzyme activity are unable to effectively convert Tamoxifen into the active form, resulting in lower levels of Endoxifen leading to ineffective treatment. A DNA test for medication can help to identify your phenotype to establish whether you are a poor, intermediate, normal or ultimate metaboliser of a particular drug. This can help to reveal the following:

  1. Which drug option to choose when deciding of a treatment regimen, but also
  2. What your dosage should be used, which can also shed light on
  3. Drug-drug interactions (other medication which could affect the metabolism of a prescription drug)

Understanding the way your body metabolises substances can be revealing when it comes to a DNA test for drugs, fertility and your susceptibility to diseases.

The Benefits of a DNA Test for Medication

A DNA test for medication like GENE-Rx™ can help you determine which medications you can take safely without risking an acute toxicity reaction.

GENE-Rx™ can help individuals achieve an understanding of their own personalised medicine. This is based on The Five Rights of Medication which are:

  1. The right patient
  2. The right drug
  3. The right time
  4. The right dose
  5. The right route

Having genetic testing in the form of a DNA test for medication can help you to understand what you may need when it comes to treating disease, even if that is not an immediate concern.

Knowledge is power and this is especially true when it comes to understanding the way your genes work in order to best treat it when it comes to diseases.

Want to get tested by GENEWAY™? Here is how it works!

 

 

DNA test for medication, DNA test for drugs, Genetic testing