I will try to not make this post too geeky but let’s enjoy some genetics. Disclaimer: it was my worst subject. I just assumed it was for specialists and researchers until I started doing my own gene testing. Now I finally feel like something is clicking! Caution: This post may be long but the moral of the story is how gene testing should become a standard of practice and nope I’m not affiliated with a specific agency or anything.
I also understand why practitioners are against it. When solely working with adults, they may tell you whatever issue and basically weather the storm. If they did have side effects, it may be drug interactions, substance abuse, liver issues…etc. plus adults know their body and manage it like with everything else… However, is that truly reassuring and hopeful? Not really. I’m not suggesting anyone is practicing without standards but sometimes it becomes a battle about what’s the best option when it’s not really clear.
Another important note with gene testing is about kids. As we all know, they are not little adults. Getting reliable information can be difficult and tiresome, so when it comes to prescribing medications, it can also be difficult. Many drugs are NOT FDA approved for children and their bodies are relatively healthy so they can get the full effect of the medication or its major side effects. However, even if you covered all your bases and took extra precautions some risks are simply unknown without gene testing. Overall across all ages, consequences can have life-long ramifications, especially in mental health, which is why gene testing should be standard.
Why Psych Providers Wouldn’t do a Gene Test or Myths
- “Well, I just start low and go slow”: it is an assumption if you start medication at a low dose, things should be okay and most of the time it is. But some of the most serious allergic reactions don’t take that much to be deadly such as angioedema with ace-inhibitors, a bee sting, shellfish…etc. Starting low can minimize harm but it can still be very deadly.
- “Adults are okay”: I fell in this category because many people are doing well on their meds without ever doing genetic testing. However, many people with a mental health history also have many trials and errors, horrible side effects, and traumatic experiences… so I also think about people who NEVER got relief or lost faith. What if they had a better treatment regimen? Gene testing may not solve all the problems but it can possibly improve adherence and favorable outcomes.
- “I still think it’s pointless”: If the patient is doing well then it’s understandable. However, even if the patient is mentally doing well, some medications have adverse reactions that can still force discontinuation; low WBC count, Steven-Johnson, or metabolic syndrome…if you have to reconsider a medication, genetic testing can be helpful in avoiding extra complications. Read about the problems with side effects vs adverse reactions.
What Gene Testing Can’t Do
- It won’t tell you what medication to take (look at FDA warning below): gene reports show how well certain pathways or enzymes can metabolize. But the body has many ways and processes to break down substances so it’s not about focusing on ONE medication. The report primarily shows how dosing may have to increase or how susceptible a person will be to side effects because of being a poor metabolizer. The FDA warning is related to prescribing medications based on the genetic report, which is true, genetic testing does not tell you what medication to take or avoid. I also think some politics may be at play with pharmaceuticals (i.e. don’t tell people to not take our meds), so of course, you have to look at these warnings and take precautions…
- Gene testing doesn’t undermine the patient: If the patient is happy on a medication that is in a red bin or suggests poor metabolizing, then continue treatment as usual. However, if side-effects occur or the medication is causing complications at least you can identify the culprit or switch to a medication that won’t make the symptoms worse.
- Testing does not make symptoms go away: this is basically the placebo effect. If you say to a patient, gene testing will tell you what med to take (which you will NOT) the patient may believe all is well when I get this ONE pill. This is why you have to look at gene testing as a metabolism report. What I explain to the family is that a gene test does not tell you anything about the med itself but rather what the body does with it. We want to minimize the side effects and mental symptoms but they still can get worse. I also look at genetic testing as another way, to be honest about a person’s prognosis and treatment.
Additional Sources & References
- DNA Tests For Psychiatric Drugs Are Controversial But Some Insurers Are Covering Them by NPR
- The FDA Warning Against the Use of Many Genetic Tests with Unapproved Claims to Predict Patient Response to Specific Medications: FDA Safety Communication
- Improving the Treatment of Depression
Welp, this subject will be getting longer so I would add the little science part later. And Happy August! I thought to add some humor from The Oatmeal to lighten the mood, I will finalize the post soon :)) Continue to do well!
Okay I’m back! just to finish the post. I’ve already discussed the importance of the Cytochrome P450 now I’ll just briefly touch on the importance of genetics. To get an idea of how serious gene testing is, I work with a psychiatrist that has tested over 700 kids. The doctor is currently seeing about 300 kids and has over 25 years of experience. I can’t explain how excited I am working with someone who is so dedicated and knowledgeable with kids. This has made my confidence indescribably grow whereas before I would’ve normally avoided children. They are now my most awesome and coolest group to work with and I couldn’t be more grateful. Let’s get back into genetics:
The Basics of DNA
A chromosome is where genetic information (the genome) of a cell is organized, stored, and retrieve or the DNA (deoxyribonucleic acid) molecule of an organism. Humans have 46 single chromosomes, 23 paired (one set from each parent). The DNA in a cell is not a single long molecule. It is divided into a number of segments of uneven lengths. At certain points in the life cycle of a cell, those segments can be tightly packed bundles known as chromosomes. During one stage, the chromosomes appear to be X-shaped.
Every fungus, plant, and animal has a set number of chromosomes. For example, humans have 46 chromosomes (23 pairs), rice plants have 24 chromosomes, and dogs have 78 chromosomes.
A gene is a segment of DNA that provides the cell with instructions for making a specific protein, which then carries out a particular function in your body. Nearly all humans have the same genes arranged in roughly the same order and more than 99.9% of your DNA sequence is identical to any other human.
Still, we are different. On average, a human gene will have 1-3 letters that differ from person to person. These differences are enough to change the shape and function of a protein, how much protein is made when it’s made, or where it’s made. They affect the color of your eyes, hair, and skin. More importantly, variations in your genome also influence your risk of developing diseases and your responses to medications.
More Love About DNA
To put it nicely, the human genome has about 20,000-25,000 “coded” genes and between 2 humans, we share about 99% of the genetic materials. The problem? Mutations. These mutations can occur at birth or are technically noticed whenever and for many different reasons. There’s really no cure or treatment, it may not even be a problem, but mutations can cause the body to have diseases, conditions, adverse reactions…etc. So with regards to medications, there can be good and bad outcomes because it’s not a ONE size fit all situation. Now we have some science to prove it or at least improve the treatment. I also like this analogy:
If the genome were a book, every person’s book would contain the same paragraphs and chapters, arranged in the same order. Each book would tell more or less the same story. But my book might contain a typo on page 303 that yours lacks, and your book might use a British spelling on page 135—”colour”—where mine uses the American spelling—”color.”
DNA is not your destiny. The way you live influences how your genome works.
Back to Gene Testing
My last point about this subject is how this genetic testing is going towards the future. I had a colleague tell me how he used a gene test to help the doctor pick a blood pressure medication for his wife. I never even thought about testing for other conditions but how cool! Overall, genetics and everything about DNA is a relatively new area of science and I’m excited to see where this can lead providers, maybe someone can start having their own genetic consultation business! I didn’t want to make this post more tedious, I hope more people will be at least be open to it, especially for patients that have failed multiple drug trials. For more information about gene testing also check out these additional websites:
- Mayo Clinic: have some great simple information for patients and clinicians.
- The Carlat Report suggested the research may be minimal but it can still provide hope: If we were to hold the GeneSight test to the usual standards we require for making medication decisions, we’d conclude that there’s very little reliable evidence that it works. On the other hand, some of you will probably want to try it out, especially for those patients who have insurance that will cover the cost of the test. If you do order it, reserve it for patients who are most likely to benefit, including patients who have failed to respond to multiple medications (which could be caused by ultra-rapid metabolism, causing drug levels to be too low), and patients who have had lots of side effects (potentially caused by slow metabolism, causing drug levels to be too high).
- Use of combinatorial pharmacogenomic testing in two cases from community psychiatry by Research Gate
- A Typical GeneSite Report and Educational Resources by GeneSite
