What if we could genetically test for IBD carrier status?

[Mitch.Connors]

Hi all. First post. I'll give you some background as to where I'm coming from here. I've had Crohn's for 19 years, some of it has been pretty terrible, not all though. I'm well controlled right now.

I'm Ashkenazi Jewish, as I'm sure (looking at the statistics for IBD) a good number of you are as well. Dating has been terrifying for me. I want kids, but I know that if I pass my disease on in a way that I feel was reckless, I'll never forgive myself. My level of fear about this has already contributed to the demise of one relationship, and has left me puzzled about how to proceed. There's shared culture with other Jewish people, but then there's this metaphorical lurking monster if I were to have kids.

I'm currently in law school, and decided to use one of my final papers to explore a thought experiment. It's being written about the ethical and legal issues that might come up if we could genetically test for IBD. Currently, my understanding is that we can't (I looked into this early on when dating) due to the limited understanding of the disease... But what if we could?

Would we treat it like Tay Sachs, resulting in altered mate selection behavior? Maybe more like CF? I'm not even sure what people do there, roll the dice? What if we could test embryos? What about during IVF egg harvesting, would we discard affected eggs or keep them?

My thoughts on this started as, "Oh, it would be nice to voluntarily get tested for peace of mind." The more I've thought about it though, the more I'm seeing reasons why we might want to mandate not allowing reproduction to occur after we've reached a probability threshold that a child would have IBD... Which kind of starts to go down this weird road where I feel like I'm arguing for eugenics. It's not where I expected my thoughts to go.

Some other thoughts:
The less people that eventually have the disease via altered procreation prompted by testing, the more financially burdensome it will be to live with, as therapeutic treatments would eventually get orphan drug status. Similarly, in the biologics realm, with less drugs being developed, patients would have nowhere to turn eventually if they develop antibodies.

Testing would increase the stigma of having the disease by decreasing (in the long term) the number of individuals afflicted.

Testing could lead to children born with IBD eventually feeling like they shouldn't exist, had only their parents known to test. Is this something that happens with CF? I think that would be a precedent for this line of thought.

I could keep going, but I think you see where my thoughts are generally. I apologize for having to gesture type this on my phone, hopefully it turned out legible.

Please don't take any offense to any of what I've written, like I said, this is a thought experiment that is being developed into a paper based on a hypothetical genetic test that I'm unaware is even on the horizon.

Please share any and all thoughts you nay have on this subject. Things like, would you want to test yourself or spouse/finance/boyfriend/girlfriend as a carrier?
What would you do with that information?
Do you worry about passing on IBD if you have it?
Have you passed on IBD? If so, what are your thoughts on that?
If you were newly pregnant and knew the disease had been passed on, what do you think you'd do? Similarly, if you're a guy and your spouse or s/o was in such a situation, what would you do?

I'm looking for all viewpoints... and it's ok to hate my thoughts on this and say so, just tell me why please.

This is more than just a paper topic for me, underlying this paper is a personal struggle with the fear of passing on my disease.

Thanks in advance!

Mitch

 

[eleanor_rigby]

I think the stats for IBD parents having children who go on to develop IBD as well is around 10%. However, that statistic is of little comfort to me as I've had IBD passed on to me, and unfortunately I am a significantly worse case than my father. Perhaps if I had no family history of IBD I would not find it all that concerning. But due to my personal situation, I do worry about future children of mine going on to have it. I previously wanted children before my diagnosis but now I am very doubtful about it as I too would feel guilt even though it wouldn't really be my fault. I also am not sure how I would look after children when I am unwell.

If we could test embryos and discard them if they had IBD then I would definitely do it and I would discard them because I would not want my children to lead future lives of pain. However, I don't know if this could ever happen as environmental factors are important as well as genetic, so I am not sure they could ever guarantee an embryo would develop IBD. But if they could I would discard.

Likewise, I am someone who if I had an embryo tested and it was positive for downs syndrome I would discard as well. It's not that I don't think lives are valuable with conditions such as these and others you can test for, it's just me personally I don't think I could cope with it.

I'm sure people will comment though is you could get an embryo tested for everything and then they may wind up getting hit by a car at 15 years old etc. But I guess if we could discard over knowing for certain that an embryo would get a serious illness then I would.

 

[Scipio]

I think you are putting too much emphasis on the genetic component as a cause of Crohn's. Genetics certainly plays a role but only a partial one. In this study of twins, 29 pairs of identical twins where at least one of the twins had Crohn's were examined. In only 4 of those pairs did both twins have Crohn's. https://www.ncbi.nlm.nih.gov/pubmed/20848478

That's a higher rate than would be observed in 29 pairs of unrelated people, but it also means that in the large majority (86%) of identical twins both did not come down with the disease despite having identical genes.

Crohn's very likely comes about through a complex interplay of genes, environment, diet, lifestyle, gut bacteria and other bacteria exposures, unknown factors, all combined with a dash of bad luck. It's not a straight-up genetic disease like Tay-Sachs or CF. By focusing solely on the genes you are likely missing the Crohn's forest due to just one tree.

 

[my little penguin]

I agree- there isn't just one disease crohns
Which is why some are worse than others and some respond well to different types of meds
It's the perfect storm some genes some environment etc...
There is nothing to say that you can't just adopt
But again you need to realize children are not perfect neat packages
They are very lovable but very messy all the same

My son was Dx with crohns at age 7
No family history at all
He also has many other things others don't have
Kids are messy and are not just a "disease " or diseases


Avoiding due to what may or may not happen is pointless
At this time no one can predict the future so all children or life is a leap of faith

Try to enjoy it
Bumps and all

 

[Mitch.Connors]

I think the stats for IBD parents having children who go on to develop IBD as well is around 10%.

Thanks for the reply. Do you by chance remember where you read that probability?

I think you are putting too much emphasis on the genetic component as a cause of Crohn's. Genetics certainly plays a role but only a partial one. In this study of twins, 29 pairs of identical twins where at least one of the twins had Crohn's were examined. In only 4 of those pairs did both twins have Crohn's. --link removed because I'm a new member--

That's a higher rate than would be observed in 29 pairs of unrelated people, but it also means that in the large majority (86%) of identical twins both did not come down with the disease despite having identical genes.

Crohn's very likely comes about through a complex interplay of genes, environment, diet, lifestyle, gut bacteria and other bacteria exposures, unknown factors, all combined with a dash of bad luck. It's not a straight-up genetic disease like Tay-Sachs or CF. By focusing solely on the genes you are likely missing the Crohn's forest due to just one tree.

Of course you're right that there is more to IBD than just genetics. Thank you for the study link btw. That's helpful information. I'm very much aware of where the research on what causes Crohn's currently is, but the issue in my mind is that unless we know what the trigger is, and can avoid triggering the disease, avoiding the genetic predisposition is my current solution. With that said, it could be that by the time a genetic test existed, we'll know what the trigger(s) is/are and can avoid them - rendering the whole thing moot - but I can't write a research paper that says, "If we had embryonic testing for IBD and/or a test for IBD carrier status, we might also know how to avoid triggering the disease, so therefore, in conclusion, we should wait and see."

I agree- there isn't just one disease crohns
Which is why some are worse than others and some respond well to different types of meds

I've heard this theory from doctors, that one day we'll realize that what is currently mostly 2 diseases, Crohn's and UC, is really more like 30 diseases - but I can't find research that supports this. I spoke to the CCFA about it yesterday and they're going to get back to me. If you know of research that discusses this, please let me know. Thanks.

 

[Scipio]

Here is a recent study of genetic association with IBD. The conclusion of this paper is that IBD consists of three diseases (not 30!) instead of the usual two. It shows that based on genetics, UC, ileo-colonic Crohn's, and ileal Crohn's should be regarded as three distinct dieases.

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4714968/pdf/main.pdf