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Scot received two at home genetics testing kits last Christmas. He wanted to share his second test, but producer Mitch had already taken one, and Troy was adamantly against taking the test. He decided to give away his second test to one of our listeners. Seemed simple, but over the past month the Who Cares guys have been looking deeper into the realities of consumer genetic testing. What they've found is worth talking about.

The winner of the competition is listener Matt. Matt is a father with one young daughter and a son on the way. Matt wanted to take the test because he was curious about his genetic predisposition of certain health conditions and the likelihood of passing them on to his kids.

Karin Dent is a certified and licensed genetic counselor at the University of Utah. We brought Karin on to discuss with Matt the realities of consumer genetic testing and have a conversation about whether or not he still wanted to take the test. You Cannot "Un-know" Your Genetics

The first question we asked Matt was whether or not he had read the terms of service for the genetic test. He had not. It was important to share one term that many people don't think about when it comes to their genetics:

Once you obtain genetic information, the knowledge is irrevocable. You should not assume that any information we may be able to provide you whether now or as genetic research advances will be welcome or positive. You may learn information about yourself you do not anticipate. This information may evoke strong emotions and has the potential to alter your life and worldview.

According to Karin, this is something a person should think about taking the test. The goal of genetic counselors is to help people understand the medical, familial and psychosocial implications of genetic data and how it can impact their health and overall well-being.

She explains to her clients they can't "unknow something." Once you learn you may be genetically predisposed to a health condition, you will always know that bit of information. It may change your life in ways you don't realize.

Karin says as a patient and consumer, you have the right to not know something just as much as you have the right to information about yourself. A DNA Test May Not Provide the Answers You Seek

The main purpose of genetic counseling is to make sure the patient is fully aware of the limitations, benefits and risks associated with genetic testing. Many people are like Matt, and looking for a potential genetic predisposition they may have. Unfortunately, genetic tests today don't test for every single condition.

Karin suggests that if a person is wondering if there is a specific genetic condition you are curious about, make sure the test you are taking actually provides results for that condition. Tests may be limited in the diseases and conditions they test for. No test on the market covers everything. Additionally, most tests available will only provide results for a small subsection of known genetic factors that may contribute to developing a condition. Your DNA is Not Your Destiny

Matt is specifically curious about conditions like Parkinson's disease as well as a predisposition to obesity and diabetes.

Most conditions these at-home genetics kits report on are complex conditions that form in adulthood. While there may be a research backed genetic predisposition for these conditions, lifestyle and environmental factors play a large role in whether or not a person will develop the condition.

"[The test] gives you an assessment," says Karin, "but it isn't a black and white result."

Despite how these tests are marketed, there is more involved in the development of a condition like obesity.. While a limited set of genes may suggest a predisposition, the diet and lifestyle of a person likely plays a bigger role in whether or not a person becomes overweight.

"One thing I like to tell everyone I meet with, patients, clients friends, is that your genetics is not your destiny." says Karin "Even if this came back and said you have an increased risk or there's an increased association with obesity based on the genetic factors that you have, remember, that is only a small subset of the genetic contributions we know currently that contribute to obesity."

There's a limitation on the information genetics test can provide. The results are not - and should not - guide your healthcare plan. These test results should not replace routine healthcare screenings. Just because your genetic results say you have a reduced chance of developing prostate cancer, that doesn't mean you should stop getting your screenings.

As such, some professionals have begun to refer to direct-to-consumer genetic testing as "recreational genomics." Meaning, the results of the test may be interesting, but shouldn't guide how you approach your health. You Are Ultimately Testing Your Whole Family

After getting your genetics results, you may be faced with not only a personal dilemma but an ethical one as well. If you found out you have an increased risk of a certain cancer, that can have a huge impact on your relatives too.

"When you take a test, you're testing a family," says Karin.

It's rare that a genetics test will find something that only impacts one person. You share much of the same genes as your parents, siblings, and children. The results you receive may be present in others. Some members of the family might not want to know. On the other hand, if you find something is there an obligation to tell the rest of the family? It's important to consider what you are willing to share with these people, and how it will impact them

Matt has had discussions with his wife about how this information may impact their family. She might have to deal with his genetic results as a wife, and as the mother of their kids. The two of them have discussed how they would approach those topics as a family. He is also considering how he will share his results with his brother. There Currently Isn't a "Professional" Option

Direct to consumer testing is unique in the genetics world because it is a test that targets healthy people. These tests are often marketed as a way to keep healthy people healthy by giving them knowledge about themselves so they can take the steps necessary to prevent different health conditions.

Clinical genetic testing isn't typically for "healthy" people. Clinical testing is used to find the cause of a severe health condition or birth defect already present in a patient. There currently isn't a readily available clinical test for healthy people who are merely curious about their genes.

There are "adult healthy screens" available in some clinical settings, but these are often very specific tests that are screening for specific conditions for rare circumstances.

With this in mind, genetic counselors do not typically suggest getting an at home test due to the limitations of the information these tests can provide. Consumer genetics testing companies are ultimately targeting you as a consumer, not a patient. There Is No Rush to Get Tested Today

Karin personally refuses to take an at-home genetics test despite her genealogically minded father's urging. For Karin, she feels there are too many limitations in the testing right now and the information it may provide is not of any value to her.

"[A direct-to-consumer genetics test] is not going to tell you anything that will change your life in a positive way," says Karin. She has met with people that have regretted what they have learned from these tests. They feel that it has changed a part of their life that they can't get back. There's a time before they learn something, a time after.

With that in mind, Karin explains that there should be no rush to go and get your DNA tested today. Unlike a lab value, your genes don't change. You will have the same genes five, ten, fifteen years from today. As genetic research advances there may come a time when the results given by genetics testing will be more valuable - and perhaps cheaper. There's no reason you can't wait to get the test later in your life. Will Matt and Scot Take the Test?

After all of this discussion with a professional, it comes down to this: Will they still take the test?

Matt still wants to take the test. He has spent a lot of time considering the realities of this kind of testing. He understands the limitations. He understands he can't unknow his results. He knows his test will impact not just him, but his whole family.

But for Matt, he reasons that he's still young. Knowing his genetics may be able to help him better understand steps he can take moving forward in his own life. He's thought about what he would do with the information and his kids. He's making an informed decision about his genetics, and that's what Karin supports.

After spending the last few months considering it, Scot has decided he isn't going to take the test. For him, he was moved by Karin's discussion of not being able to "unknow" something. He works hard to live a healthy life. He has a good understanding of his family history. He feels that there is nothing the test will tell him today that would positively impact his life.

Scot may consider taking the test in the future, but he recognizes that there's no pressure to take the test today just because it's trendy. Just Going to Leave This Here

On this episode's Just Going to Leave This Here, Scot challenges Troy to guess what's wrong with his ear and Troy hates shaving so much he jokingly considers laser hair removal. Talk to Us

If you have any questions, comments, or thoughts, email us at hello@thescoperadio.com.

Interviewer: A group of concerned scientists have raised the question: Should we be able to genetically engineer people? We'll talk about that next on The Scope.

Announcer: Examining the latest research and telling you about the latest breakthroughs. The Science and Research Show is on The Scope.

Interviewer: Scientists have called for a moratorium on genetically engineering human embryos until the safety and ethics have been worked out. I'm talking with Dr. Dana Carroll, a distinguished professor of biochemistry at the University of Utah. He and his colleagues have made their voices heard in a commentary that was just published in the journal Science. Dr. Carroll, why is this topic coming under scrutiny now?

Dr. Carroll: The CRISPR technology is very, very simple in its design and application and it's turned out to be extremely effective. More and more laboratories are now using this technology for a variety of purposes for research, even for agriculture. Because it's so easy and so many people are using it, the issues, which were sort of in the background for a number of years, have now moved to the front and amongst them is this issue of potentially engineering the human germ line.

Interviewer: One of the points under discussion right now is germ line modification. Can you explain what the germ line is and what that means?
Dr. Carroll: The thing that makes the germ line changes more serious than things you might do to somatic cells is that the changes are permanent and heritable. So if mom and dad are carrying mutations that could cause disease in their offspring, the idea is that the genome engineering would allow the correction back to what we would call the normal DNA sequence of that potential disease gene.

Interviewer: Yes, well exactly, and that's why this technology is so exciting is that we may be able to eliminate inherited diseases within a family. Correct?

Dr. Carroll: That's right.

Interviewer: So you told us about the promise of this technology, but what are people worried about? Why is this under discussion right now?

Dr. Carroll: There are a few things to be concerned about. One, from a scientific perspective is that, although I said we can make very specific targeted changes in the genome, the reagents that we are using, these nucleases, are not 100.00% specific. There may be other changes that occur, not just at the gene we're trying to target, but elsewhere in the genome. So we need to perfect the technology to a point where we can be quite confident that we aren't making things worse at the same time we're making things better.
There is some concern that because the technology is easy, that it will begin to be used for what you might call trivial purposes, like a couple trying to endow their children with what they consider favorable characteristics: blonde hair, blue eyes, athletic prowess.

Interviewer: How close are scientists to being able to do these types of experiments?

Dr. Carroll: In humans . . .

Interviewer: In humans, yes.

Dr. Carroll: This sort of manipulation has been done in a lot of different organisms, including mice and rats and pigs and cows and even monkeys. So the technology is ready to be applied to humans.

Interviewer: I think one thing that is interesting is that there is not even consensus among informed scientists. I think you're in the camp that can see a future where this technology is permissible, under the right control, but there are others who think that we shouldn't go forward with this technology at all.

Dr. Carroll: The commentary that was published in Nature basically said, the authors stated that they could never envision a situation where germ line genome modifications should be allowed or would be necessary. I think that's a little bit short-sighted. Like I said, I don't know what the best candidate genetic diseases are for this kind of genome engineering, but I'd love to hear from physicians and other biologists who are sort of closer to the human disease arena to see what they have to say about it.
The other thing is that we don't want to get into a situation where the public in general, individuals around the country and around the world, think that scientists are just trying to make monsters. We want to engage the public to see what the public thinks about it. If it turns out that there's, at this stage, close to zero public acceptance of going forward, then I think scientists should be governed by that.

Announcer: Interesting, informative, and all in the name of better health. This is The Scope Health Sciences radio.

Interviewer: A new practical method that will boost the productivity of genetic engineering labs, coming up next on The Scope.

Woman: Examining the latest research and telling you about the latest breakthroughs, The Science and Research Show is on The Scope.

Interviewer: Using principles borrowed from population biology, Dr. Luca Brunelli, an assistant professor in pediatrics at the University of Utah, has developed a rapid, inexpensive, one step method for isolating rare DNA recombinants. Dr. Brunelli, what motivated you to come up with this method?

Dr. Luca Brunelli: Our interest in these techniques really stems from our research focusing both on human genetics and mouse genetics and our interest in trying to use mice to elucidate key mechanisms of human disease.

Interviewer: This addresses an intermediate step in genetic engineering.

Dr. Luca Brunelli: Yes. We have described this technique that we call F.P.E., founder principle-driven enrichment, in E. coli in a technique that is commonly called recombineering or recombination mediated genetic engineering, which is an intermediate step that allows, for example, among many other things to produce the targeting vectors that are required to produce genetically modified mice.

Interviewer: What were some of the problems that you were trying to address?

Dr. Luca Brunelli: If one thinks of genetic combination, the general idea is that these events are rare. The key problem is the general conception that it's really impossible to isolate that one event out of a hundred thousand unless you link a marker to that event because of how rare it is.
In reality, we have found that by applying principles from population genetics, specifically the founder principle, you are able to very effectively, rapidly, cheaply, and simply isolate these rare variants without using markers. What population genetics and the founder principle tell us is that when you establish founder populations, meaning very small populations, from large populations some of these alleles, some of the genetic background that existed in the original population, either is wiped out or is enriched, is fixed in this new population.
As long as you have a screening technique, which in our case was P.C.R., to be able to detect whether in liquid cultures your event is present or not, what happens when you decrease the size of that culture to, let's say, 5000 cells is that in some of those liquid cultures you will still have one recombinant, but you've actually enriched for your recombinant for your rare event. So, going through two or three enrichment cycles such as this that I've just described you can actually isolate your variant, bring it to a frequency that is 1 in 20, 1 in 50, such that you can easily plate your liquid cultures on an agar plate and isolate the clone easily.

Interviewer: And just pick individual ones.

Dr. Luca Brunelli: Yeah, just picking the ones.

Interviewer: Basically, you're taking your original pool that has your recombinant in it, then you're diluting it out.

Dr. Luca Brunelli: How many days it's going to take to isolate your rare variant and how many P.C.R.s you're going to want to do really depends on your preference. In our manuscript we've actually included a mathematical model with a web available calculator that allows a researcher to sort of import their desired level of effort, if you will, and days that they want to do the isolation in, and be able to reselect the preferred conditions. The calculator will advise them on what kind of enrichment, what kind of dilution, to use under those circumstances.

Interviewer: Right. How much quicker is it?

Dr. Luca Brunelli: To generate something seamless you need to introduce both selection markers and counter selection markers, so at a minimum ten days. With our approach that takes us down to two to five days at the most.

Interviewer: Oh wow. And I imagine it's cheaper.

Dr. Luca Brunelli: Cheaper also, yes, because you save reagents, antibiotics, a number of...

Interviewer: I'm struck by this as really a very straightforward technique.

Dr. Luca Brunelli: It is, and what's striking in a way is that it had not been described before.

Interviewer: Exactly.

Dr. Luca Brunelli: I have to say that once we were developing this method and we thought to include the full mathematical model of this, we went to a mathematician to help us out with that. The first comment from the mathematician was well, this is so easy, why has nobody else thought about this before.

Interviewer: Yeah.

Dr. Luca Brunelli: It was extremely easy for the mathematician to understand that if you decrease the number of cells below a number that breaks the symmetry of how rare and more common variants are present it's pretty clear that you can enrich for those. Interviewer: What's the advantage over other selection techniques like zinc fingers or crispers?

Dr. Luca Brunelli: With zinc fingers and crispers people have used a different approach which is to create double stranded breaks in the DNA so the DNA would effectively make these changes at a much higher frequency. But the double stranded break, it's easy to understand, also creates, if you will, stress on the DNA and so has a chance to produce what people call off target effects . . .

Interviewer: I see.

Dr. Luca Brunelli: . . . making changes and modifications also in regions of the DNA where you wouldn't want to have those changes.

Interviewer: What are the applications for this method?

Dr. Luca Brunelli: One of the direct implications would be to ask the question whether what we have done in E. coli can also be replicated in mouse embryonic stem cells.
Other possible applications that we see that are really exciting are in recombineering pipelines with the idea of studying gene function, large scale modifications also, for example, to produce biofuels, so bacteria acquire certain characteristics that will enable them to perform better at certain functions like to do production of a biofuel or cleaning water or whatever you might think of.
Although it's outside of the medical field, we're certainly interested in some of those applications, and we are considering possibly collaborating with some investigators who work in those fields.

Woman: Interesting, informative, and all in the name of better health. This is The Scope Health Sciences Radio.