By R Carter
Estimates are 30% of the population has one or more genetic variants which affect metabolism or bio-availability of over-the-counter and prescription medications. For this reason these individuals are classified as either high or low metabolizers.
If your in that 30%, depending on your genome variants and medications taken, you may have side effects or unpredictable results. All of which run counter intuitive to the labels, high and low metabolizer.
A low metabolizer may have trouble converting a medication into its bio-active form, producing symptoms of being under medicated. Yet in others a low metabolizer may only partially convert a medication, creating intermediate forms which can build up as toxins. Or having converted a medication to its active form, further metabolism into harmless waste products may be blocked also resulting in toxic concentrations which produce other symptoms.
A high metabolizer may convert a medication into its active form so rapidly a small dose of medication produces profound results which are sometimes short lived. Or a high metabolizer may simply clear a medication out of their system so quickly its desired effects are hardly noticed or simply short lived.
Often multiple gene variants are required to produce these types of results and even then, detecting a variant doesn’t mean a defect in metabolism. Some medications are metabolized by other more generic enzyme systems. Or a metabolic pathway may be duplicated in other areas of your system which do not carry these genetic variants. Simply put, our bodies have redundant backup systems for clearing foreign substances from our system.
Genetic variants have become so common that drug manufactures are now required to provide extensive testing on some medications to identify and document which variants play a role in altering dosage amounts and frequency.
With regards to chronic pain suffers, about 10% of the population have one or more genetic variants which affect the metabolism of opiates, also producing high or low metabolizers. But these variants tend to produce more low metabolizers than high metabolizers, the most frequent of which are defects in metabolizing codeine and methadone based analgesics.
If your doctors in the past have prescribed benzodiazepines as part of managing the stress of having poor results from opiates and now those types of medications have been denied due to the 2016 CDC’s position on opiates and benzodiazepines, pharmacogenetic testing can also identify genetic variants which may indicate you are a low metabolizer of benzodiazepines. Such information can go a long ways towards assuring your prescriber on the safety and efficacy of a balanced approach in using both medications or at least adjusting your opiate dosage so you can return to a productive and gainfully employed life.
The cost of testing has dropped dramatically in the last ten years with the average cost after insurance being $300.00. If you have Medicare Part A and B, in most cases the test will cost you nothing and some labs will perform the test for $300 even if Medicare benefits are denied, making the test affordable for most people. It’s important to note that getting the test performed is often just the first step, have the test results read and interpreted may also be required as most primary care providers are not trained in interpreting the test results. It should also be remembered that these test results do not always a smoking gun on pin pointing a specific cause for a set of symptoms. Genetic testing for a specific disease or condition is always given as a set of probabilities, so if your tests says you have a 60% chance of having problem X, the only way to put that into a real world context is to have a geneticist review the test results which is often an additional expense.
If you don’t respond to your medications as expected or have results and side effects which can be consistently reproduced, there’s a 33% chance you have a genetic variant as the cause. Consult with a physician about your concerns and request pharmacogenetic testing. Don’t be surprised if your physician at first seems less than convinced, this is a new field of medicine and even recent graduates from medical school are not up to speed on its benefits. Be persistent and firm if you believe these test may benefit you and educate your doctor on the cost / life benefits.
If you’re asking questions like, where can I get my genome sequenced? The next question to ask is, do I want whole genome sequencing which is quite expensive or do I want genotyping which simply identifies the variants you have in a specific area of your genome and is considerably less expensive. If genotyping then your next question is, genotyping for what purpose? If that purpose is to identify possible alterations in drug metabolism, then common Google search terms like “pharmacogenetic testing labs” will provide the best results. Using this search phrase I found these links.
All medical grade testing requires a doctor’s order to perform and performing the test is only half the solution, depending on what your testing for and the results your test may need to be read and evaluated by a specialist in pharmacogenetics. Some of these labs provide these specialist who will consult with your doctor on how to best utilize the test results.
- Alcala Labs
- Ally Clinical Diagnostics
- ARUP Laboratories
- Assurance Laboratories
- Assurex Health
- BioGenetysis Inc
- Boston Heart Diagnostics
- Center for Molecular Cancer Diagnostics
- Children’s Hospital of Philadelphia – Genomics Diagnostic Laboratory
- Cincinnati Children’s Hospital Medical Center
- Coriell Life Science (Gene Dose)
- Duke University Clinical Labs
- Epinex Diagnostic Laboratories
- Eurofins Genomics
- Exceltox Laboratories
- Firefly Diagnostics (Chromacare)
- Geisinger Medical Laboratories
- Genetic Technological Innovations
- Gnome Diagnostics
- Gravity Diagnostics
- Gulfstream Diagnostics
- Health Care Providers Laboratories
- Highline Laboratories
- Indiana University Genetics Laboratories
- Integra Laboratories
- Iowa Institute of Human Genetis
- Iverson Genetics
- Kailos Genetics, Inc
- Lab Express
- Lab Genomics
- LabSource, LLC
- LabTest Diagnostics
- Lotus Laboratories
- Luxor Scientifi
- Mayo Medical Laboratories
- Medical College of Wisconsin (Advanced Genomics Laboratory
- Millenium Health Laboratories
- Molecular Testing Labs
- Next Molecular Analytics
- NextGen Laboratories
- Oregon Health & Sciences University
- Pathway Genomics
- Patient Choice Laboratories of Indiana
- PersonalizeDx Labs
- Pinpoint Molecular
- Pinnacle Lab Services
- Premier Medical
- Primex Clinical Laboratories
- Prometheus Laboratories
- Proove Biosciences
- Quest Diagnostics
- Sema4 (formerly Icahn School of Medicine at Mount Sinai – Genetic Testing Laboratory
- Sorenson Genomics
- Sunrise Clinical Laboratories
- Univerity of California, San Francisco Clinical Laboratories
- Univerity of Chicago, Genetic Services Laboratories
- Univerity of Florida Health Pathology Laboratories
- Univerity of Maryland Medical Center Translational Genomics Laboratory
- Xact Laboratories