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Clinical Applications of Advanced Genetics by David Rosenthal, MD

As we know, no genetic test is ever perfect or absolute. Watch this short video as Dr. David Rosenthal discusses genetic testing in his video Clinical Applications of Advanced Genetics.


As we know, no genetic test is ever perfect or absolute.

It’s one of the problems with this genetic testing is that we wish they could predict 100% of the time what you’re going to do when you make that decision to try medication. The genetic testing is particularly useful for people who’ve been treatment resistant. But a lot of people do the testing at the beginning and don’t wait until the patient is resistant before trying it. But you know, so often people want the test to be perfect and absolute. And obviously, no genetic test ever is going to be that way.

Given that environment influences genetic expression, and we have so many different variables to look at, which is why you’re doing integrative psychiatry to try to get at root causes of problems and not just looking at one test.

Gene X Environment Interaction
You can see that the black line there represents a childhood trauma and depression score. So obviously, if you’ve been exposed to enough childhood trauma, your risk of becoming depressed at some point in your life is significantly increased over and above that of somebody who doesn’t have childhood trauma. But now, when you introduce MTHFR variants, and have difficulty methylating folic acid, you can dramatically increase the risk of becoming depressed as an adult.

SLC6A4 Genotypes
This just illustrates, this is a slide I showed in the last lecture about really just summarizing the different genotypes, the two short alleles being the poor responders. Another significant thing when you have two short alleles and elevated stress-induced cortisol, these people have the greatest cortisol fluctuations in response to stress when you see somebody with two short alleles. I often think about using phosphatidylserine or something to help regulate cortisol levels.

Ion channel genetic variants are common across many mental health conditions
These ion channel variants are common across several different mental and emotional conditions. So here are some of the traditional ways to tone down that system is using heavy duty mood stabilizers.

Second generation antipsychotics, Lamotrigine, when we have our bipolar two patients, Lithium. But Omega-3 fatty acids also tone down excessive glutamate activity, and so does N-acetylcysteine and magnesium. So magnesium, Omega-3’s and N-acetylcysteine are all good at lowering excessive glutamate activities, especially in somebody who’s not bipolar or not schizophrenic, where you really don’t want to go to any of those heavy-duty mood stabilizers.