Preimplantation Genetic Testing for Polygenic Disorders Called PGT-P
From the Show: RSC NJ - Fertility Talk
Summary:
Air Date: 12/27/22
Duration: 10 Minutes
Dr. Alan Martinez discusses pre-implantation genetic testing for polygenic disorders called PGT-P.
Transcription:
Melanie Cole (Host): Welcome to Fertility Talk with RSCNJ, the Reproductive Science Center of New Jersey. I'm Melanie Cole. Joining me today is Dr. Alan Martinez. He's a specialist in reproductive endocrinology and infertility at the Reproductive Science Center of New Jersey, and he's here to discuss pre-implantation genetic testing for polygenic disorders PGTP. Dr. Martinez, always a pleasure to have you with us. So let's discuss this. First of all, I'd like you to just tell the listeners what is pre-implantation genetic testing as a whole.
Dr Alan Martinez: Thank you, Melanie. I'm glad I could have an opportunity to talk about this today. So pre-implantation and genetic testing or PGT, this technology was brought about in order of a way to screen embryos. And the embryos are made in the laboratory, they are grown out or cultured until they meet a high level of development. And then the embryology lab staff, they will biopsy an embryo and then the embryos get frozen. The genetic material is screened most commonly, and historically for aneuploidy or the number of chromosomes, which is the common reason why individuals may have miscarriages.
And you can also be used for single gene disorders such as cystic fibrosis and such. And then more recently, our topic today is looking at kind of a probability or a health score of the embryos. And this is a particular topic of conversation today.
Melanie Cole (Host): Okay, so then tell us about PGTP, this new offering where an embryo health score that you just mentioned is obtained for polygenic conditions. Tell the listeners what polygenic conditions are. And how this new type of testing can predict that risk because boy, this is such an interesting topic.
Dr Alan Martinez: Yes, so the polygenic screening of embryos, what we're referring to is conditions that we don't have an exact mutation, genetic cause, but rather there's many factors, hence the word polygenic. And so it can be conditions such as diabetes, it can be mood disorders, maybe schizophrenia risk, maybe heart disease, and so all of these conditions do not have an actual single gene that is responsible for this. And as a result what happens is you have a situation where you may have embryos, you implant them, they're normal genetics as far as like down syndrome and those kind of things, numerical chromosomes.
But maybe later on in life of strong family history. Maybe this embryo is, a really high chance of heart disease and having heart issues, whereas this other embryo may not. And so that's the whole idea behind the screening for polygenic conditions.
Melanie Cole (Host): So is it true Dr. Martinez, that infertile couples an infertile population have more of a risk of cardiovascular disease, cancer, diabetes? due to this clinical practice of selecting more metabolically active, these not quiet embryos for transfer. Can you tell us a little bit about this, because I'm not sure I completely understand it, but is there an increased risk in this community? Is it stress related? Can you tell us about that?
Dr Alan Martinez: Yes. Many of these conditions may have an association, I guess is the best way to describe it. It's not a cause and effect, meaning that you have an infertility, either male or female or both patient, they're coming, they're struggling getting pregnant. Could something inherently with either the egg or the sperm, be causing some of the associations or the higher prevalences of these conditions? Or is it that or is it a combination of the infertility treatment itself? So many of these things, we don't have a solid clinically statistically significant increase, but there are some associations that we see.
And it probably is inherent of the egg and the sperm themselves and the type of embryo they make more than the treatment. But this is kind of delving into probabilities that may allow patients if they so desire. to look at these particular conditions as an element of choosing the embryo that they want transferred in the baby that they would like to have.
Melanie Cole (Host): And we're gonna get a little bit more into that, but when is it indicated to do pre-implantation genetic testing for these polygenic disorder?
Dr Alan Martinez: Well, I think that is a controversial topic right now, the clinicians and the scientists that are pro this technology argue that it's up to the individual patient as many things should be, I think. And so if you have a grandfather, a uncle that died of early heart attacks in the males. Maybe that condition is considered to be more important for those patients and maybe they would use this technology. There are no current guidelines to this because this is such a new entity and it's a probability score. It's not as if it's a guaranteed chance that they're gonna end up with such and such condition.
So those countering who are against or maybe frowning upon this technology, say, well, these individuals can still lead overall, healthy life. Probably they can have a similar, maybe normal lifespan, but this technology is a little bit too much selection of these particular conditions and traits that aren't really related to the pregnancy rate and them having a child. So you can see that both sides have valid points in some ways, and I think it's, as this technology becomes more prevalent, I think it's gonna really depend upon just counseling from the physicians, counseling from providers, and then a shared decision making with the patients and partners or the individuals involved in wanting to conceive a child.
Melanie Cole (Host): I think you said it right there, shared decision making and really being aware of what this is all about and discussing it with you, Dr. Martinez, because you're so knowledgeable about so many things ASRM, this was a debate topic. It was well attended. Can you speak about some of the other ethical issues at hand? Why might some people you said there are pros and cons? There are people on both sides of the fence of this, as there are many things these days, but this one has some very interesting twists and turns that can even be seen as an increased disparity in health between wealthy and poor into the next generations access to care.
Whether we can actually do anything about these predictions, heart disease, diabetes, I mean, there's so many things. Can you discuss just a few of the ones that were discussed at the recent convention?
Dr Alan Martinez: I think that the core argument there was in populations and individuals that can take part in this technology or can screen embryos and want to screen embryos, that I think that the cost of the actual treatment is sometimes a barrier for certain populations and certain individuals. It's on a case by case basis, but the technology is advancing to where this is becoming more afford. Now you can say, all right, well, is it right to select for these kind of traits? Should we be able to take this a step further and select for eye color or, a hair color, skin tone, what have you, different physical traits that may Be associated with some sort of advantage.
So you could argue about that. You could argue, saying that, okay, you use this technology well, what if there's a high prevalence of being screened out of fertility coverage, right? Because you have a high risk, because, okay, you make a lot of embryos, you have a strong heart disease history, you have a strong cancer history in your family. So you could somehow see how maybe somebody can be screened or be denied some coverage potentially because of the absolute risk. So I think that, it's gonna be an interesting development of this as, particular companies start to delve into the probability scores and these polygenic conditions.
And I think that, time is really gonna tell of whether, once you have the technology is how many people are actually gonna use it and if it's gonna be long-lasting. And I think that's where we're uncertain at this.
Melanie Cole (Host): I think so too. Gosh, this is so interesting. As we get ready to wrap up here, what are some things you'd like. Couples that are considering IVF to think about if they are going to proceed or consider proceeding with this type of genetic pre-implantation testing and what you tell them when you counsel them about suppose they do find out that heart disease is in this particular embryo or diabetes at a young age, type one.
What do they do with that information? When we do genetic testing as adults, Dr. Martinez, we talk about prophylactic mastectomies who are watching for symptoms of Parkinson's, but this is kind of on a different level. So I'd like you to just offer your best knowledgeable advice about what you want couples to think about when they're considering this type of testing.
Dr Alan Martinez: Well, I think first and foremost, the main primary reason why a person undergoes. PGT or, pre-implantation genetic testing is to screen for Anuplaty. We know that is the highest risk of miscarriages, of couples not being able to hold onto a pregnancy, having miscarriages, having, unhealthy children or not getting pregnant. So I think that needs to be the overarching goal of the pre-implantation genetic testing is to screen for the highest probability. Aspect that will allow that patient and partner to achieve their dream of being a parent.
Once you figure out that the embryo is normal, genetics, then looking at the family history, Of that couple looking and trying to decide whether it's important to screen these embryos. I think that that has to be a careful decision. I think you have to think long and hard of whether, if you have a, 60% chance of having something versus 80% chance it's a percentage probability, but it's not a definitive yes or no. That embryo is gonna have that in the future. So this is where, like I said, shared decision making and talking to your provider, talking with your partner, and making the best individual decision for yourself.
Melanie Cole (Host): Great information and such a fascinating topic. Dr. Martinez, thank you so much for joining us, and I really hope that you'll come back on and update us as some of these issues come to light and you see what the trends are. This was so interesting. Thank you again. And for more information, please visit fertilitynj.com to get connected with one of our providers. That concludes this episode of Fertility Talk with RSCNJ, the Reproductive Science Center of New Jersey. I'm Melanie Cole.
Melanie Cole (Host): Welcome to Fertility Talk with RSCNJ, the Reproductive Science Center of New Jersey. I'm Melanie Cole. Joining me today is Dr. Alan Martinez. He's a specialist in reproductive endocrinology and infertility at the Reproductive Science Center of New Jersey, and he's here to discuss pre-implantation genetic testing for polygenic disorders PGTP. Dr. Martinez, always a pleasure to have you with us. So let's discuss this. First of all, I'd like you to just tell the listeners what is pre-implantation genetic testing as a whole.
Dr Alan Martinez: Thank you, Melanie. I'm glad I could have an opportunity to talk about this today. So pre-implantation and genetic testing or PGT, this technology was brought about in order of a way to screen embryos. And the embryos are made in the laboratory, they are grown out or cultured until they meet a high level of development. And then the embryology lab staff, they will biopsy an embryo and then the embryos get frozen. The genetic material is screened most commonly, and historically for aneuploidy or the number of chromosomes, which is the common reason why individuals may have miscarriages.
And you can also be used for single gene disorders such as cystic fibrosis and such. And then more recently, our topic today is looking at kind of a probability or a health score of the embryos. And this is a particular topic of conversation today.
Melanie Cole (Host): Okay, so then tell us about PGTP, this new offering where an embryo health score that you just mentioned is obtained for polygenic conditions. Tell the listeners what polygenic conditions are. And how this new type of testing can predict that risk because boy, this is such an interesting topic.
Dr Alan Martinez: Yes, so the polygenic screening of embryos, what we're referring to is conditions that we don't have an exact mutation, genetic cause, but rather there's many factors, hence the word polygenic. And so it can be conditions such as diabetes, it can be mood disorders, maybe schizophrenia risk, maybe heart disease, and so all of these conditions do not have an actual single gene that is responsible for this. And as a result what happens is you have a situation where you may have embryos, you implant them, they're normal genetics as far as like down syndrome and those kind of things, numerical chromosomes.
But maybe later on in life of strong family history. Maybe this embryo is, a really high chance of heart disease and having heart issues, whereas this other embryo may not. And so that's the whole idea behind the screening for polygenic conditions.
Melanie Cole (Host): So is it true Dr. Martinez, that infertile couples an infertile population have more of a risk of cardiovascular disease, cancer, diabetes? due to this clinical practice of selecting more metabolically active, these not quiet embryos for transfer. Can you tell us a little bit about this, because I'm not sure I completely understand it, but is there an increased risk in this community? Is it stress related? Can you tell us about that?
Dr Alan Martinez: Yes. Many of these conditions may have an association, I guess is the best way to describe it. It's not a cause and effect, meaning that you have an infertility, either male or female or both patient, they're coming, they're struggling getting pregnant. Could something inherently with either the egg or the sperm, be causing some of the associations or the higher prevalences of these conditions? Or is it that or is it a combination of the infertility treatment itself? So many of these things, we don't have a solid clinically statistically significant increase, but there are some associations that we see.
And it probably is inherent of the egg and the sperm themselves and the type of embryo they make more than the treatment. But this is kind of delving into probabilities that may allow patients if they so desire. to look at these particular conditions as an element of choosing the embryo that they want transferred in the baby that they would like to have.
Melanie Cole (Host): And we're gonna get a little bit more into that, but when is it indicated to do pre-implantation genetic testing for these polygenic disorder?
Dr Alan Martinez: Well, I think that is a controversial topic right now, the clinicians and the scientists that are pro this technology argue that it's up to the individual patient as many things should be, I think. And so if you have a grandfather, a uncle that died of early heart attacks in the males. Maybe that condition is considered to be more important for those patients and maybe they would use this technology. There are no current guidelines to this because this is such a new entity and it's a probability score. It's not as if it's a guaranteed chance that they're gonna end up with such and such condition.
So those countering who are against or maybe frowning upon this technology, say, well, these individuals can still lead overall, healthy life. Probably they can have a similar, maybe normal lifespan, but this technology is a little bit too much selection of these particular conditions and traits that aren't really related to the pregnancy rate and them having a child. So you can see that both sides have valid points in some ways, and I think it's, as this technology becomes more prevalent, I think it's gonna really depend upon just counseling from the physicians, counseling from providers, and then a shared decision making with the patients and partners or the individuals involved in wanting to conceive a child.
Melanie Cole (Host): I think you said it right there, shared decision making and really being aware of what this is all about and discussing it with you, Dr. Martinez, because you're so knowledgeable about so many things ASRM, this was a debate topic. It was well attended. Can you speak about some of the other ethical issues at hand? Why might some people you said there are pros and cons? There are people on both sides of the fence of this, as there are many things these days, but this one has some very interesting twists and turns that can even be seen as an increased disparity in health between wealthy and poor into the next generations access to care.
Whether we can actually do anything about these predictions, heart disease, diabetes, I mean, there's so many things. Can you discuss just a few of the ones that were discussed at the recent convention?
Dr Alan Martinez: I think that the core argument there was in populations and individuals that can take part in this technology or can screen embryos and want to screen embryos, that I think that the cost of the actual treatment is sometimes a barrier for certain populations and certain individuals. It's on a case by case basis, but the technology is advancing to where this is becoming more afford. Now you can say, all right, well, is it right to select for these kind of traits? Should we be able to take this a step further and select for eye color or, a hair color, skin tone, what have you, different physical traits that may Be associated with some sort of advantage.
So you could argue about that. You could argue, saying that, okay, you use this technology well, what if there's a high prevalence of being screened out of fertility coverage, right? Because you have a high risk, because, okay, you make a lot of embryos, you have a strong heart disease history, you have a strong cancer history in your family. So you could somehow see how maybe somebody can be screened or be denied some coverage potentially because of the absolute risk. So I think that, it's gonna be an interesting development of this as, particular companies start to delve into the probability scores and these polygenic conditions.
And I think that, time is really gonna tell of whether, once you have the technology is how many people are actually gonna use it and if it's gonna be long-lasting. And I think that's where we're uncertain at this.
Melanie Cole (Host): I think so too. Gosh, this is so interesting. As we get ready to wrap up here, what are some things you'd like. Couples that are considering IVF to think about if they are going to proceed or consider proceeding with this type of genetic pre-implantation testing and what you tell them when you counsel them about suppose they do find out that heart disease is in this particular embryo or diabetes at a young age, type one.
What do they do with that information? When we do genetic testing as adults, Dr. Martinez, we talk about prophylactic mastectomies who are watching for symptoms of Parkinson's, but this is kind of on a different level. So I'd like you to just offer your best knowledgeable advice about what you want couples to think about when they're considering this type of testing.
Dr Alan Martinez: Well, I think first and foremost, the main primary reason why a person undergoes. PGT or, pre-implantation genetic testing is to screen for Anuplaty. We know that is the highest risk of miscarriages, of couples not being able to hold onto a pregnancy, having miscarriages, having, unhealthy children or not getting pregnant. So I think that needs to be the overarching goal of the pre-implantation genetic testing is to screen for the highest probability. Aspect that will allow that patient and partner to achieve their dream of being a parent.
Once you figure out that the embryo is normal, genetics, then looking at the family history, Of that couple looking and trying to decide whether it's important to screen these embryos. I think that that has to be a careful decision. I think you have to think long and hard of whether, if you have a, 60% chance of having something versus 80% chance it's a percentage probability, but it's not a definitive yes or no. That embryo is gonna have that in the future. So this is where, like I said, shared decision making and talking to your provider, talking with your partner, and making the best individual decision for yourself.
Melanie Cole (Host): Great information and such a fascinating topic. Dr. Martinez, thank you so much for joining us, and I really hope that you'll come back on and update us as some of these issues come to light and you see what the trends are. This was so interesting. Thank you again. And for more information, please visit fertilitynj.com to get connected with one of our providers. That concludes this episode of Fertility Talk with RSCNJ, the Reproductive Science Center of New Jersey. I'm Melanie Cole.