Genetics of Congenital Heart Disease – PediaCast 199
Dr. Kim McBride joins Dr Mike in the PediaCast Studio to discuss the genetics of congenital heart disease. We explore hypoplastic left heart syndrome, aortic stenosis, and coarctation of the aorta. Evidence is mounting of a strong genetic basis for these disorders, and we’ll take a look at what this means for early diagnosis and intervention. We’ll also tackle questions related to genetic counseling and the services provided by the Center for Molecular and Human Genetics at Nationwide Children’s Hospital.
Genetics of Congenital Heart Disease
Hypoplastic Left Heart Syndrome
Coarctation of the Aorta
Heart Diagrams for Reference
Announcer 1: This is PediaCast.
Announcer 2: Welcome to PediaCast, a pediatric podcast for parents. And now, direct from the campus of Nationwide Children's, here is your host, Dr. Mike!
Mike Patrick: Hello, everyone, and welcome once again to PediaCast, a pediatric podcast for moms and dads. It is Episode 199, boy, we are close to 200, for February 15th, 2012, and today we're going to be talking about the genetics of congenital heart disease.
It's kind of a complex topic today and it has the potential to be pretty heavy on the science, but we're going to make a genuine effort here to keep things understandable and interesting for those of you without strong science backgrounds. But we're still going to try to go into enough detail to provide some satisfaction for the clinicians in the audience as well. I know it's something that we attempt to do in every episode of the program, but I think it's particularly important to provide that balance today.
So what exactly are we going to talk about was the title alluded to complex structural abnormalities of the heart that children are born with.
You know, with most disease processes, we take the disease and we primarily look forward, how do you diagnose it, how do you treat it, what are the potential complications, what's the prognosis, and today is going to be a little different. We're actually going to take a look backward and explore why some types of congenital heart disease happen in the first place, and we'll talk about the genetic factors that are involved, and then we'll explore how understanding the genetics of congenital heart disease can help us improve outcomes for babies who are affected by these.
And to help me explore these topics, we have a great guest lined up for you today in the studio. Dr. Ken McBride is a physician scientist with the Center for Molecular and Human Genetics here at Nationwide Children's Hospital. He's going to be joining us in just a couple of minutes to talk about these things.
I do want to remind you, if there's a topic that you would like us to talk about, it's easy to get a hold of us. Just head over to pediacast.org and click on the 'Contact' link. You can also email firstname.lastname@example.org or call the voice line at 347-404-KIDS, that's 347, 404, K-I-D-S.
I also want to remind you, the information presented in every episode of PediaCast is for general educational purposes only. We do not diagnose medical conditions or formulate treatment plans for specific individuals, so if you have a concern about your child's health, make sure you call your doctor and arrange a face-to-face interview and hands-on physical examination.
All right. Dr. Ken McBride is a physician investigator with the Center for Molecular and Human Genetics at the Research Institute in Nationwide Children's Hospital and an Assistant Professor of Pediatrics at the Ohio State University College of Medicine.
He received his medical degree from the University of Saskatchewan, completed a residency in Pediatrics at the Mayo Clinic and fellowships in Clinical Genetics and Biochemical Genetics at Baylor University College of Medicine. He also received his Master's Degree at Baylor in the Clinical Scientist Training Program.
Dr. McBride is the Co-Director of the Cardiovascular Genetics Clinic and also participates in the Pediatric Genetics and Metabolic Clinics where he cares for pediatric and adult patients with a special interest in genetics involving the heart. His research focuses on the genetics of congenital heart disease, which is why he stopped by the PediaCast studio to talk to us today.
Welcome to the show, Dr. McBride.
Ken McBride: Good morning.
Mike Patrick: So University of Saskatchewan, did I say it right?
Ken McBride: That's close enough.
Mike Patrick: That's how Yankees say it, right?
Ken McBride: Canadians might call it University of Saskatchewan. We have a bit of a cut with our vowels and make it a little bit shorter…
Mike Patrick: Sure.
Ken McBride: …softer.
Mike Patrick: Are you from Canada originally?
Ken McBride: I am from Canada originally.
Mike Patrick: Great. Well, welcome to the show. We appreciate you stopping by. We have some complex things that we're talking about today, and I guess a good place to start, we throw around some words, 'congenital heart disease', 'inherited heart disease' and we contrast those with 'acquired heart disease'. Could you just give us some definitions of what these various terms mean?
Ken McBride: Sure. We'll go back to do a little bit of basic genetics first to guide you through the next part of the topic.
Congenital heart defects are something that you notice immediately at birth or shortly thereafter. They may be inherited or they may not be. They may be caused by environmental things. Inherited diseases can show up at birth or you may not notice them until much later in life. Acquired disease is something that you get later on in life and it may have a genetic component to it as well.
Mike Patrick: What types of congenital heart diseases, and in particular, congenital heart diseases that are inherited, are you studying?
Ken McBride: I'm studying a specific group that's put together as the left ventricular outflow tract, so that's the part of the heart that involves flow of blood from the lower pumping chamber up out through the valve and then into the aorta. The type of defects in this group include something called aortic valve stenosis, coarctation of the aorta, and hypoplastic left heart syndrome.
Mike Patrick: Let's go back just a second, and those of you out in the audience, you're just going to have to think back to your high school Biology days a little bit. The human heart has two sides, the right heart and the left heart. The right heart pumps blood to the lungs and the left heart pumps blood to the rest of the body. So we're talking about the left heart, which is the bigger, thicker, stronger pumping chamber because it has to pump to the body. So as you go on the left…did I say that right? I said "left," didn't I?
Ken McBride: That's correct.
Mike Patrick: It's in my brain, 'Did I say "right" or did I say "left"?' The left heart is what we're talking about, which is pumping to the rest of the body, and if you're in the left side of the heart from the atrium, which is the upper chamber, it goes through the mitral valve, and then the left ventricle to the aortic valve, and then to the aorta, and then out to the body.
If you're having trouble visualizing this, check out the show notes at pedicast.org. We're going to have some diagrams for you just to make it a little bit easier, and if you want to head over there while you're listening, you can get a nice visual of what this part of the heart looks like.
Ken McBride: Yeah, it would be very helpful.
Mike Patrick: Yeah. So why is it important that we study these diseases?
Ken McBride: Congenital heart defects are very common. They make up one of the most common birth defects in general. Birth defects occur roughly around 3 or 5% of all people who are born. Heart defects occur roughly in about 1% of people, so this puts it into the realm of other common diseases you might hear about such as autism, which occurs in 1 in 110 is the most recent figure.
On top of that, congenital heart defects are sometimes quite deadly. The leading cause of infant mortality, that's the death cause for people who are aged one year or under, top cause is birth defects, and heart defects make up about 25% of that group. So these are important birth defects.
Now on top of that, there are some kinds of birth defects, and one which I study called bicuspid aortic valve. It's a different formation of the aortic valve; rather than having three parts or leaflets to it, it's got two. It's actually very common. You can find that in 1 or 2% of people who are adults. Many people don't know about it, but when they do get into trouble, they can get into some very serious trouble where they may need open heart surgery later in life.
Mike Patrick: One of these heart defects that you talked about is the hypoplastic left heart syndrome. What exactly is that?
Ken McBride: It's actually a complex of things that happens because of probably a defect of the aortic valve.
Hypoplastic heart syndrome comprises a narrowing or a total closure of the aortic valve, that's the valve that controls blood flow from the lower chamber out into the aorta, a similar problem with the mitral valve which controls blood flow from the upper chamber on the left side to the lower chamber. Because there's no flow of blood through either of those valves, then the left ventricle, the lower pumping chamber on the left side, can't develop very well, so it's very small, and because there's no blood flow that goes out into the aorta, it also doesn't develop very well, so it is small.
So these are children who have a very severe heart defect; fine at birth, because of how the circulation works when you're inside the mother, but as soon as that circulation changes, these children become ill very rapidly, and if they're not identified and have medical and surgical treatment in the first week or so of life, they could die.
Mike Patrick: For the doctors and nurses in the audience and those with Biology degrees, there's a couple of structures in the heart, the foramen ovale and the ductus arteriosus, and these are things that shortly after birth close, but in babies who are born with hypoplastic left heart syndrome, they're really dependent on those things to provide flow to the rest of the body, so it's important that we try to recognize these defects as soon as possible so that those structures that are supposed to close don't close, or at least we can delay the closure until we can get things fixed. Otherwise, it could be deadly.
Ken McBride: That's correct. These are a group of defects that are classified as ductal-dependent. As soon as that ductus closes, which it normally does in most people, is when they get into trouble, so one of the therapies is to identify that before that duct closes and then give medications to try and keep that open to buy you some time for surgery.
Mike Patrick: Sure. And I have to apologize, I didn't mention this before the show to you, but there is a little bit of controversy out there with the name of this, whether it should be called hypoplastic left heart syndrome or is it a defect, and it's interesting that some folks are arguing over the nomenclature.
Ken McBride: It is. I've weighed in on this one as well because it's very confusing. As a geneticist, you like to reserve the term 'syndrome' for something that has a specific cause, usually a genetic cause, sometimes an environmental cause that then leads to a variety of downstream problems. So you have one thing that causes a bunch of different stuffs.
When you think of typical syndromes like Down's syndrome, for instance, due to a problem with having an extra Chromosome Number 21, you may have intellectual disability, you may have specific kinds of facial features, you may have a heart defect. People argue that that syndrome may not be particularly applicable for hypoplastic left heart. I've argued otherwise in saying it is a syndrome, although it's not in the typical sense of the word that people use.
Mike Patrick: Sure. Yeah. The hypoplastic left heart syndrome that we talked about, and you also mentioned bicuspid aortic valve is another abnormality in that left ventricle outflow tract, what's the definition of aortic valve stenosis and coarctation of the aorta? What do those terms mean?
Ken McBride: Aortic valve stenosis is an inability for that valve to be able to open properly, so the bloodflow through that valve has less flow through it or the heart has to work harder to get the same amount of flowthrough.
Coarctation of the aorta is actually a narrowing of the aorta, usually in a very specific, discrete spot, right at where that ductus, that's the connection between the pulmonary side to the systemic side occurs, there is a definite, discrete narrowing there so the blood can't flow through the aorta. Same kind of a narrowing idea as the aortic valve.
Mike Patrick: Sure. Like the hypoplastic left heart, do we think that that originates with the problem with the aortic valve or is that something a little bit different?
Ken McBride: The working idea that we have through research we've done in our lab and from other labs, these are all related to each other because of maybe a problem in how the aortic valve develops and also how the aorta itself develops, at least that section that occurs as it comes off of the heart.
The hypoplastic left heart syndrome, we think, is an aortic heart disease, because if we can find fetuses during pregnancy where we can see an aortic valve narrowing or a stenosis early in the pregnancy, say, 18 weeks or 20 weeks, then we are following these individuals along during their pregnancy, we notice that the left ventricle becomes progressively smaller and smaller and the aorta doesn't grow. So we think probably then it's the aortic valve disease and the rest of these things are secondary.
Interesting thing, if you take a look at people who have just an aortic valve stenosis or a bicuspid aortic valve is they often have troubles with the aorta just above where the valve is. So it's something about the formation of that valve and that part of the aorta that seem to be linked. These problems are where the aorta can get bigger or dilate and can lead to a rupture which is called an aortic dissection.
It's interesting, too, that when we take a look at families who have one of these things, so we find people who have a bicuspid valve and we start looking at their relatives, we can see people who have just that dilation and dissection of the aorta but not the valve problem. We can see some people have both the valve problem and the dissection as well.
The other thing, too, that's very important, I think, for families is that if you have a child with a hypoplastic left heart or a coarctation of the aorta, the relatives can have a bicuspid valve, and we've done this before and done echoes on parents and on siblings, we can find a bicuspid valve in those individuals in 5 or 10% of the time.
Mike Patrick: Is that why we started to think that maybe there is an underlying genetic factor involved with this?
Ken McBride: I think that's what started it off, yes.
When we started looking at these families, we were saying, well, we should be finding other people with hypoplastic left heart. Those families are very rare. Or if we're looking at people with coarctation of the aorta, we should be looking at more families who have just that. We can find them, but more often actually when we start looking at these families and we can see people who might have a hypoplastic left heart syndrome, there may be someone who's got a coarctation of the aorta. We can see someone else in the family, an uncle, who has had a bicuspid aortic valve.
And we were taking a look at many of these families over and over again and we kept seeing the same pattern where you could see any one of these defects that involved that left ventricular outflow tract in the families. Not necessarily the same one, but repetitively we see this. And if we were looking for other kinds of heart defects, they weren't occurring very commonly in there, so there seemed to be some sort of a link about these defects within families.
Mike Patrick: Now, prior to going down that road of there being a genetic factor, it was thought that maybe something in the environment was causing this to happen. And I actually have a little bit of a personal experience with this.
A good friend of mine from college, and we remain friends to this day, their first baby was born with hypoplastic left heart, and this was maybe 15 years ago or so and he did pass away and didn't survive the surgery to try to correct that, but I recall they lived in a rural area and there was some concern that it seemed like that area, that particular area, had a higher rate of congenital heart defects than other areas that you may look at, so there was a question of whether fertilizers or there's something in the environment that might be having a factor here.
Is that still thought or do we think it's just genetic? Or are there environmental causes? Or can the genetics and environment influence one another? What's your take on that?
Ken McBride: Good question.
Environmental causes can be very hard to pull out even more so than genetic causes. If we were to take a step back and look at heart defects in general, we know that there are a few things that can cause heart defects.
For instance, one of the more commonly known ones are fetal alcohol syndrome, or FASD is what the term is used now. People who have exposure to alcohol during the pregnancy have a higher rate of certain types of heart defects. Usually it's a defect where there's a hole between the lower chambers of the heart that are called ventricular septal defects.
If the mother has diabetes and it's not well-controlled during pregnancy, that baby is also at higher risk of having heart defects.
For hypoplastic heart syndrome, there has not been as good data, so we see these clusters of things. For instance, in Wisconsin, we'd noted that people who lived in highly industrialized cities had a higher rate. I've done similar searching in Texas where we looked at birth defect registry data there and we could find that in certain counties in Texas, we noticed that there were increased rates of these things. What actually leads to that increased rate, we don't know yet.
There was one very large, nicely-done study back in the '80s called the Baltimore-Washington Infant Study where they took a look at all babies who were born in the Baltimore and Washington, D.C. area and they took a look at detailed backgrounds of these pregnancies. They think that perhaps organic solvents might increase your risk but weren't able to pin it down any further than that.
Mike Patrick: Yeah. Could it be that you start out with a genetic propensity for this so if you have a certain gene that maybe then an environmental factor could turn it on or off?
Ken McBride: That's certainly possible, although at this point we don't know what those might be.
Mike Patrick: We just don't understand it.
Ken McBride: Yes.
Mike Patrick: Tell us a little bit about your research concerning the genetic influences for the development of these defects.
Ken McBride: Again, we talked about this a little bit earlier in the podcast, we're finding families where we seem to have an increased rates of these things where we would expect by chance. We are finding that if you had one person in a family that had a heart defect and we looked hard enough, say, they had hypoplastic left heart, we could find about 20% of relatives, going back out not only to the parents and the siblings but aunts, uncles and grandparents, about 20% of the time we could find at least one person who had another heart defect. We thought, 'That's pretty strong evidence that this is a strong genetic component.'
We started off with some very traditional techniques. We'd take a look at families, we would collect all the people in the family and then look to see if we could find what chromosome you might find this gene, and we do tests that are called 'linkage analysis' where you try and trace bits of DNA. If you're familiar with "CSI", for instance, where they're coming up with these DNA profiles on people, you can use these same profiles and track them through families and see if you can find if one of those little markers that the "CSI" guys use might actually track with your heart disease. Hasn't been quite as successful with that technique because there's a very complex genetics involved.
Mike Patrick: Sure.
Ken McBride: We are now using some newer technologies to do sequencing. We think back about the Human Genome Project and the sequencing that was done on that using old technology, so it took 10 years to get one individual. We now have the ability to actually sequence an entire individual in two weeks.
Mike Patrick: That's incredible. I mean, I remember when I was in college, they were still working on the first one. It took years.
Ken McBride: It's evolved rapidly. No, it's exciting for me; I can use these technologies and it's actually proved a lot more fruitful at finding genes.
Mike Patrick: Yeah. So basically you're saying this family has a high number of these defects, so let's try to find an area on their chromosomes where they're all abnormal compared to the general population, and then you zero in on that?
Ken McBride: We actually try and track it. We may find a region that says, well, this region on Chromosome, let's say, 1, tracks through this family the same way that the heart defects track through this family. That might be a large region with which we wound up with.
Mike Patrick: Sure.
Ken McBride: And then you have to narrow down within that region, there may be 100 or 200 genes in there, to try and pick out the one you think is the most likely culprit.
Mike Patrick: Yeah. How close do you think you are to figuring that out?
Ken McBride: A lot better in the last couple of years.
Mike Patrick: That's the million-dollar question.
Ken McBride: Yeah. The studies I've done, I've been at it for 10 years to try to do these linkage studies in families, since we've developed the sequencing technology here at Nationwide Children's, we actually now have one family which we've located the exact gene we think is causing the problem, and we are now just queuing up our other families.
Mike Patrick: To see if they have that gene.
Ken McBride: To find that gene or if they have something different. So it's become a lot more exciting in the last couple of years.
Mike Patrick: Yeah. Now, apart from just the interest of finding this gene, there's actually a good reason to be able to identify if someone has this gene and are they at risk for it. Talk to us a little bit about why it's important to actually identify these things for families on a clinical level.
Ken McBride: Sure.
One of the basic questions we get asked when someone comes to the clinic is, 'I have had something in my family that we think is a genetic problem. What's my child with having a child with the same condition?'
The way that we're doing that currently, because we actually don't know what causes hypoplastic left heart, is to say, well, let's take a look at the last several hundred families who had a child with hypolastic left heart who then go on to have another child. How often do we see that second child also have a heart defect? So we can give you a rough risk, but that's really rather crude because it applies to a big group of people but it may not apply to that person individually who's sitting in front of you.
If I can find out exactly what causes the heart defect and then can test for that on the family, I can tell them a lot better what their risk might be. So I might be able to say, 'You know, your risk is pretty close to zero,' or 'You know, you've got a genetic defect here that's a high risk.' That makes big differences for families if they're trying to plan out how many children they want or if they want more children.
Mike Patrick: Yeah, just what are the risks of this happening.
Ken McBride: Right.
Mike Patrick: What about early identification in terms of if you can early identify that a baby might be affected. Is there a way that we could intervene to help them survive earlier?
Ken McBride: Certainly. The traditional techniques now is just to rely on the regular ultrasound that you get during pregnancy. They're not bad. They may pick up, say, 30 or 50% of people who might have a heart defect, which is helpful, but then there's a lot where they're missing. And as I explained before, you may find a person who's got this aortic valve problem who then goes on to have the heart defect, but finding that aortic valve problem to start with can be very hard.
If we know what causes the disease and can test, we're going to be a lot more accurate. And that's quite important for a couple of reasons.
One is that if we know someone has a heart defect and we can get them to deliver in a place where they can attend to the baby quickly as opposed to waiting for them to get sick, we'd do an awful lot better.
There is also now a few groups across the country who are trying to intervene during the pregnancy. If we say that we have this aortic valve problem but no hypoplastic left heart, is there something that we can do to that valve so that baby then doesn't go on that could develop to full-blown hypoplastic left heart syndrome?
Mike Patrick: So if the aortic valve that we talked about, stenosis or atresia, where you have decreased flow through that valve, this is really kind of cutting-edge science sort of stuff…
Ken McBride: Yes.
Mike Patrick: …if you could go on in while the baby is still inside mom and with a balloon dilate that valve so that you increase flow through it, then maybe you can avoid the left ventricle from not developing fully or maybe prevent the aorta from not developing fully and maybe prevent the whole defect. I mean, you still have an abnormal aortic valve, but you won't have these other problems associated with it.
Ken McBride: Yes, so the surgery then becomes an awful lot easier for the guys after the baby is born and also he'll have a better outcome with it.
And people are doing this in Boston, for instance. There's a group that's trying this. There are not many people who qualify for the type of intervention, but the ones who do qualify, they have had not bad success at being able to open that up and have a better outcome later.
Mike Patrick: We should point out that doing this, of course, has its own risks, and you certainly worry about the spontaneous abortion and the baby dying because of the procedure that you're doing.
Ken McBride: Yes.
Mike Patrick: So it's not something that you do as a cavalier kind of thing. You just…specific cases.
Ken McBride: Very careful selection and being done by a group of people who really know what they're doing.
Mike Patrick: Yeah.
Now, do you see in the future that there could perhaps then be universal genetic screening, just like we do a newborn screen and try to pick up PKU and sickle cell disease? Someday could it be that we could do a screening for congenital heart defects in terms, of course, they were going to be born with the defect itself, but just to say, 'Hey, this is in your family. This is something you have to look at,' or not really?
Ken McBride: Well, I think personalized medicine or personal genomic medicine is out there. We're not ready for it right now because we still have a great deal of difficulty deciphering what all these different genetic changes might mean for an individual.
But the type of technology I'm using in the research lab where we're sequencing someone's entire genome is now out there and available clinically for people to use, so potentially, you could have your entire genome sequenced for you, put on your little flash drive, and you carry that with you for life. And as people understand what these changes mean, they'll be able to predict better what might happen to that person.
Potentially, we're there. A little science fiction at the moment, but it's out there.
Mike Patrick: Right. Now, talk a little bit about genetic counseling. I guess it would be really easy for that genetic counselor if the person's whole genome, we knew exactly what genes did what and what they were risked at, if you were going to have a baby with this person, what are your chances at X, Y, and Z. We're not quite there yet, but what is the role of genetic counseling today?
Ken McBride: I think genetic counselors play an extremely important role for families who are worried about a genetic disease.
A genetic counselor is someone who's got the basic science background, so they have a bachelor's degree and then they have a master's degree specifically in the genetic counseling part. Their role is to try and take a look at individual families and see what's there. They do something called drawing a pedigree or your genealogy and looking through it for diseases and then trying to help you come up with what might be a relative estimate of risk for any particular disease that you might be worried about, and then help educate the family and the individual about this disease and guide them along in what might be the best decision for them with this information.
Mike Patrick: And we obviously have genetic counseling services here at Nationwide Children's Hospital. How do folks get in touch with that, get plugged into that service?
Ken McBride: We have a large group of very good genetic counselors here at Nationwide Children's. At the moment, for someone who's interested in genetic counseling services for, say, something like a heart defect, would be to have a referral to our genetics physician at the clinic, and with the help of a physician and a counselor would be able to advise you on information on your family.
Mike Patrick: We'll put a link in the show notes to the genetics clinic here at Nationwide Children's Hospital, and it has location and phone numbers and referral information and all that business on it so it will be real easy for folks to get in touch.
And you don't just see folks from Central Ohio. If someone from Missouri didn't have the genetic counseling program close or if they wanted a second opinion, you take folks from all over the place, right?
Ken McBride: We certainly do, and actually get contacted by email because I'm doing research in this area from all over the place. As an example, in the last week I've had someone from Oregon and someone from Pennsylvania email me about worries they had about their families.
Mike Patrick: Sure.
Ken McBride: And I have physicians and other researchers from essentially around the world who contact us, I'm thinking New Zealand, South Africa, Australia, Belgium, Germany, on a regular basis.
Mike Patrick: All right, let's say there's a family out there who says, 'Wow, we have this. There is a cluster of folks with these heart defects in our family.' Are you looking for more families to get involved with your study?
Ken McBride: Definitely. If you have a history of this or it's in your family, and this would be aortic valve stenosis, bicuspid aortic valve, coarctation of the aorta, hypoplastic left heart syndrome, we'd be very interested in seeing you. My focus at the moment has been in families where we have people who have more than one person in the family.
And it doesn't have to be confined necessarily to this specific set of heart defects. If there are other people who have a different kind of heart defect running through their family, we'd be very interested in hearing from you.
Mike Patrick: Sure. And again, they can get a hold of you just going to that genetics page. We'll also have the link to your profile at Nationwide Children's Hospital and there's also contact information there as well. So if you just head over to pediacast.org and look for the show notes for Episode 199, we'll have all that information for you there.
Well, we really appreciate you stopping by the studio today to talk about these things. Before you go, one last question for you, and we ask all of our guests the same thing. I really have a passion for families doing stuff together around the table that don't involve television screens and video games and just really putting your minds together and having some fun as a family, and in our house, we play a lot of board games. So we just ask all of our guests what your favorite board game is now or as a kid, just to put you on the spot.
Ken McBride: Well, I guess as a kid, I grew up playing Risk.
Mike Patrick: Oh, sure. Yeah.
Ken McBride: We had a blast with that. We'd get friends together and sometimes we'd play two and three world Risks, so we'd each bring our games over and tack them all on together. We do that as a family now. We sometimes play Risk. I think our favorite games probably for me and my kids, I've got two teenagers, would be Backgammon. That's a board game.
Mike Patrick: You know, a couple of other people have mentioned Backgammon, and I've never played it, so I think we need to check that one out because we love to play games. And it's a strategy game, right?
Ken McBride: It's very much a strategy game.
Mike Patrick: Yeah. That sounds great. Now, if you like Risk, have you done Axis & Allies?
Ken McBride: You know, I tried that when I was a teenager, and I haven't actually gone back to it very much.
Mike Patrick: It's very complicated and it takes a very long time. My son got it for Christmas and we've played a couple of times, and it's a marathon session, but he beats me every time we play. [Laughter] Risk is a little easier. There's less going on. Or there's still a lot going on.
All right. Well, once again we appreciate you stopping by. I just want to, and of course we want to thank all of you for taking time out of your day to allow PediaCast to be a part of it. We really appreciate it.
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Again, we appreciate you taking time, and until next time, this is Dr. Mike saying stay safe, stay healthy, and stay involved with your kids. So long, everybody!
Announcer 2: This program is a production of Nationwide Children's. Thanks for listening! We'll see you next time on PediaCast.