In this episode of the Conceive Baby podcast IVF and Fertility Specialist Dr. Daniel Lantsberg joins me to dive into the evolving topic of genetic carrier screening in preconception care and IVF. 

Dr Lantsberg shares valuable insights into what genetic carrier screening is and who should consider testing. We also explore how genetic carrier screening can influence reproductive outcomes and the options available to couples who are found to be carriers of genetic conditions. Dr. Lanstberg highlights the accuracy and limitations of genetic testing and discusses the future of genetic screening and potential advancements in the field. This informative episode empowers you with valuable information, enabling you  to make informed decisions.

Key Takeaways:

• Genetic carrier screening is a form of preconception care that can identify the risk of passing on genetic conditions to offspring, even if there’s no known family history of illness.
• Screening is meant for the general population and is ideally done before starting a family to maximize the available preventative options.
• Basic genetic carrier screening in Australia covers the three most common conditions and is now bulk billed by Medicare.
• Expanded screening can test hundreds of genes, offering a higher chance of detecting carrier status but at a higher cost.
• Knowledge from these tests empowers prospective parents to make informed reproductive choices, including IVF with pre-implantation genetic testing (PGT) to select healthy embryos.

About the Guest:

Dr. Daniel Lantsberg is a respected consultant gynecologist with a specialization in fertility, reproductive endocrinology, and fertility preservation. He serves as the clinical director of education at Melbourne IVF and has a rich professional background with special interests that include elective egg freezing, age-related infertility, unexplained infertility, male infertility, polycystic ovary syndrome (PCOS), endometriosis, and fibroids. Dr. Lantsberg’s commitment to reproductive health extends to his role at the Reproductive Services Unit at the Royal Women’s Hospital, as well as a senior lecturer position at the University of Melbourne’s Department of Obstetrics and Gynecology.

You can find out more about Dr Daniel Lantsberg at the links below.

Website

Facebook Page

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Egg Freezing Melbourne Instagram

0:00:40 Tasha Jennings: And to share his insights on this topic with us today is Dr. Daniel Lansberg. Daniel is a consultant gynecologist specializing in fertility, reproductive endocrinology and fertility preservation. He is also the clinical director of education at Melbourne IVF. His special interests are elective egg freezing, age related infertility, unexplained infertility, male infertility, fertility preservation, pcos, endometriosis and fibroids.

0:01:38 Dr Daniel Lantsberg: Thanks for having me, Tasha.

0:01:42 Dr Daniel Lantsberg: Thank you. What a long introduction.

0:01:45 Dr Daniel Lantsberg: I’m very humbled and embarrassed with all these unnecessary titles, but thank you.

0:02:23 Dr Daniel Lantsberg: Absolutely. So I understand what you’re saying. There’s so much confusion about what that is and the word genetics, a lot of times it sounds a bit scary and overwhelming and people have a tendency to think that everybody’s healthy in their family. So there’s no need really to go into genetics. But genetics has evolved so much over the recent years to allow us to take action to undertake preventive measures to avoid having an offspring with a genetic condition.

0:03:30 Dr Daniel Lantsberg: So in the past, couples would discover that they’re carriers of a genetic condition after having a child born with that genetic condition. But nowadays we can actually prevent this from happening. We have excellent tools, and what were previously very expensive tests now have become readily accessible for everyone to check if there are carriers before they have a baby.

0:04:17 Dr Daniel Lantsberg: The genetic Harris screening is intended for the general population. Of course, if there’s a known condition in the family, obviously, this is even more so important. But that is looking for a specific condition that is known to the family because somebody is already affected by that. But the genetic care screening is intended for the general population, for the low risk general population. That means even if you don’t have anyone sick in your family and everybody’s healthy, still, genetic carrier screening is for you. And the best time to do the genetic carrier screening test is before starting your family.

0:05:17 Tasha Jennings: Yeah. So I guess once we know that, how does that influence, particularly in the IVF setting, is where we see it a lot. I mean, there’s sometimes unplanned pregnancies in natural conceptions, but obviously, IVF is very much a planned conception of sometimes having difficulties. Where does genetic carrier screening, how does that, I guess, influence the outcomes of your IVF and where do you go from there?

0:06:12 Dr Daniel Lantsberg: And the reason we are linking genetic screening with IVF is that couples who are found to be of risk of having an affected child have an option to undergo IVF and test embryos before they place back into the uterus, before they’re transferred. And basically, by testing the embryos, we avoid transferring embryos that have the potential to create a sick baby, and that way prevent having a sick child.

0:07:20 Dr Daniel Lantsberg: So in this case, knowledge is power. Knowledge allows couples to make the best choices for themselves in the context of genetic screening. So couples who are at risk may choose one of many options that they have.

0:07:54 Dr Daniel Lantsberg: So the human genome consists of thousands and thousands of genes, and there are many genes that could be at fault. The original screening test only started for very specific conditions. So we would basically look at the whole genome, and we would only search for a very specific area in the genome that codes a very specific gene and to see if that gene is coded correctly. That was the origin of genetic carrier screening. It started off with very specific locations in the genome. And as genetics have evolved and newer tools have been introduced, we have the ability to screen for multiple genes.

0:09:13 Dr Daniel Lantsberg: That’s cystic fibrosis, spinal muscular atrophy, and fragile x. And as of late last November, so four months ago, this test is now covered by Medicare. It is bulk built, which is amazing. And that’s a huge achievement for legislation and activism that has been going on for quite some time to try to promote this test to be covered by Medicare and be accessible to all. But when we do that test, basically we uncover 20% of couples who are at risk of having genetically affected offspring.

0:10:44 Dr Daniel Lantsberg: Some panels would cover 500 genes, some would cover 1000 genes, and there are even panels that cover over 1000 genes. And the more genes you test, the more reassurance you get. And a question I get asked a lot, how much is enough? What level assurance is enough? So I don’t think there’s one size that fits all in terms of an answer to that question. But generally speaking, the panels that cover around the 300 to 500 genes normally cover about 95% of couples who are at risk of having an affected child.

0:11:59 Dr Daniel Lantsberg: And the reason for that is that there’s such high prevalence of high chance of one of them being a carrier of something, it makes sense to do the test together. And sometimes doing the test in conjunction actually makes the test a bit cheaper.

0:12:37 Dr Daniel Lantsberg: So when we look for genetic carrier screening, recessive conditions, most of these conditions, not all of them, but most of them do not impact the actual person’s health. They only will impact their offspring. There’s a very few small number of genes that should be excluded from that statement. But generally speaking, the purpose of genetic Harris screening in the context of reproduction are aimed at searching for conditions that may potentially impact an offspring.

0:13:24 Tasha Jennings: Yeah. So you’d want to get both partners ideally tested?

0:14:05 Dr Daniel Lantsberg: And if you are to do a genetic carrier screening, I would recommend doing the test together and then you can get a rebate for that test at least once. It makes the test significantly cheaper compared to, just think about it like 20 years ago, doing these tests would have been science fiction. It would have been extremely expensive, would have cost billions and billions of dollars, and nowadays they’re readily accessible for everyone.

0:15:08 Dr Daniel Lantsberg: Okay, so when we talk about PGT pre implantation, genetic testing of the embryos in the process of IVF, there are different tests we can do to the embryos. So what we do in the process of PGT is we sample a few cells from the area in the embryo called the trophoectoderm, which is the area that will create the placenta. And we rely on the fact that these cells are similar to the ones that, to the cells that will create the baby.

0:16:24 Dr Daniel Lantsberg: So one test is what the classic when people say PGT think about, which is called PGTA anaploid, a standing for anaploidy. That means we want to check that the structure of the chromosomes of the DNA are intact. There’s no extra chromosome, there’s no missing chromosome. For example, the most common genetic condition I think people can think about in this context is down syndrome or trizomy 21. Where there’s an extra chromosome, the number of that chromosome is 21.

0:17:48 Dr Daniel Lantsberg: And the lastly, PGTM, which is interlinked with genetic screening, I’ll explain. So if we do genetic screening for any couple and find that they’re both carriers of a genetic condition, for example, the most common one being cystic fibrosis, if both of them are carriers of cystic fibrosis, one in four children will be affected, will have cystic fibrosis. What we can do to prevent that from happening is do IVF, create embryos, biopsy them in the process of PGT, and we do the test called PGTM.

0:19:02 Dr Daniel Lantsberg: This method was particularly took front headlines with Mackenzie’s mission.

0:19:10 Dr Daniel Lantsberg: So if you’ve heard of Mackenzie’s mission, it was a wonderful, beautiful project undertaking by Mackenzie’s parents. Mackenzie was a baby that unfortunately passed away from a genetic condition called SmA, spinal muscular atrophy. And that was a genetic condition that could have been prevented if everybody had known that there are carriers of SMA as an example, but there could be many other genetic conditions that could have been diagnosed to be carriers of before having kids.

0:20:14 Tasha Jennings: I guess that’s what I was wondering. The next steps, if we do do genetic carrier screening for a couple, I guess the next step is really counseling on what these and understanding these results, because as you said, especially if you get all of those genes tested, we are screening for a lot of different genes there, some of which don’t have much impact at all, some of which are obviously considerably impactful to life.

0:20:41 Tasha Jennings: There to coupled to find out. I guess the next step is the embryo testing, if they want to make sure they exclude those genes.

0:21:29 Dr Daniel Lantsberg: And in cases where there’s a risk of having an affected child, the genetic counselor will go over what that genetic condition is potentially, if there are treatments for that genetic condition once the baby is born, what kind of life expectancy and what kind of symptoms that the baby may have if they were to have this genetic condition. And then they would also go over their options. Option one is doing IVF and having the genetic testing done in the process of IVF in the same way I’ve just explained through a PGTM.

0:22:39 Dr Daniel Lantsberg: But as I said, knowledge is power if you know there is a risk, you can have all the information you need to make the best choice for yourself. And there’s no judgment and there’s no right or wrong way to manage this. But as you said, you are in the field of preventive medicine, and in many ways, so am I. And if we can prevent suffering and sickness in cases where we have the option and access to the right treatments, I think that is a great approach. But the same time, it is as good as if people were to choose to have a child who has a genetic condition.

0:23:28 Tasha Jennings: Yeah, but as you said, you’re empowered by that choice and that knowledge and being able to make informed decisions.

0:23:35 Tasha Jennings: Around that for what is right for your family. So I guess looking at that in regards to, you mentioned some of the limitations around, obviously, the PGT testing. What are the limitations? I guess, and accuracies, too, is a question I get asked. How can I absolutely confirm? Because you hear those stories. Oh, they said there was an issue, and then I had a healthy baby, and then people really get concerned about the accuracy of that testing. We mentioned it with the PG testing.

0:24:13 Dr Daniel Lantsberg: The tests are considered to be very accurate, but then in no way 100% accurate. Some may quote 98% or 99%, but this is the vicinity of marginal error that can still occur in these tests, at least not today. They’re not 100% accurate, but very close to that. And if a couple would decide to take their chances without testing, the risk of having an affected child is 25%. If they do that test. And, for example, do IVF with PGTM, the risk would be one or 2%.

0:25:03 Tasha Jennings: Yes, absolutely. And I think the best thing you can do is to make informed decision, is to get counseling around the testing, because genetics can sound scary. They sound like an unchangeable part of ourselves. And I’m glad you’ve clarified that because I think there is a perception that, well, if I have these genes, I’ll get sick. Obviously, I have this disease. And as you said, there’s so many recessive genes, and these aren’t an indication that you’re going to be unwell and not even an indication that every child that you’re going to have is going to have this. It’s just the ability to help ensure that it isn’t passed on, if that’s a possibility.

0:26:07 Dr Daniel Lantsberg: And some families may be at risk and complete their family planning, being very lucky and not having any affected children. But the statistics unfortunately can overturn and it could be quite different for other families. So that’s why I have huge faith in this technology to being able to assist and inform ourselves of any potential risk for a genetic condition.

0:26:59 Dr Daniel Lantsberg: Absolutely right, Tasha. And a lot of people are for some reason afraid. They’re thinking, oh, this is going into the genetic world. We’re looking to modify babies or select only super babies. This is not the intent. This is not what we are using these tests for. We only aim by doing these tests is to ensure that the baby is not born with a genetic condition that could be life altering for both the baby and the parents.

0:27:58 Tasha Jennings: Actually, a question I haven’t flagged in here, but people say, boy, girl, is that something that you’re going to do when you do the testing? Can they choose what they get?

0:28:42 Dr Daniel Lantsberg: Yes, based on that. But those are very rare circumstances. In most cases, we will have the information but will be undisclosed to me as a clinician and also to the patient. But I’ve had patients who undergone PGT and they wanted to know the gender right after the transfer, and that is possible. So we can do an embryo transfer which is undisclosed and very early. If they’re pregnant, we can let them know the gender by revealing those documents that are sealed to us.

0:29:25 Tasha Jennings: Right, so they can find out a little bit early if they want to.

0:29:29 Tasha Jennings: Just not too early. I guess. This is such an evolving field, as we mentioned, if we had have talked about this 30 years ago, it would have been science fiction. It really would have been. And I think we’ve just made so much progress. Where do you see if you do it, all this going, what’s the new innovations coming forward and where is testing going, if at all?

0:30:40 Dr Daniel Lantsberg: But can we fix it? We already have that technology to alter genomes. That’s called CRISPR. It is not being used in IVF. It is a very powerful yet very complicated and also dangerous technology to be able to alter genes to fix them. And there’s a lot of ethical debate around using this technology. In the context of reproduction, can we alter the embryos to make them better? But in the context of disease prevention, is there a place for altering genomes? That is also a huge field of research and also ethical debate?

0:32:02 Tasha Jennings: I know it’s been such a valuable session, and I think we’ll probably have you on another. I reckon in five years, we’ll be advanced by then, so it won’t take long. We’ll be on for the next one. But thank you for taking the time to be with me today. I hope you enjoyed the episode. And be sure to download my free checklist@tashajennings.com. Au checklist to get some free little swaps and fertility rest peas there for you.

0:32:37 Dr Daniel Lantsberg: Thank you, Tasha. It was great being with you today. Thank you.