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by twic 844 days ago
Down syndrome is caused by a chromosomal aberration that comes about during formation of an egg, not a mutation. It's not possible to detect it by screening the parents' DNA.
3 comments

But it is possible to detect by screening the embryo's DNA, which is currently happening. Still I don't think this technology will reach universal adoption within the next 50 years.
You're correct, but so is the person you replied to; they wrote their comment confusingly, though.

PGT-A testing is very common in IVF and will catch Down Syndrome. Essentially no births from IVF (a growing percentage of all births) have Down Syndrome.

As you mention, this testing is done after an embryo has been created.

Perhaps this is why screening of the amniotic fluid to detect things about the parasite within the host is common?
What parasite?
It's not just amusing (and for some, uncomfortable) terminology. Pregnancy stimulates the mother's immune system in ways normally associated with fighting a parasite, and the fetus defends itself using techniques that successful parasites use.

"Embryo implantation sets off a process that ultimately turns off a key pathway required for the immune system to attack foreign bodies. As a result, immune cells are never recruited to the site of implantation and therefore cannot harm the developing fetus."

...

"it gives a satisfying explanation for why the fetus isn't rejected during pregnancy, which is a fundamental question for the medical community" - https://www.sciencedaily.com/releases/2012/06/120607142244.h...

Have a google around for similar papers. It's a fascinating topic that we've only begun to fully understand in the last decade or so.

I get it, based on a variety of medical phenomena, you can draw parallels between an unborn baby and a parasite. If thats your point, then fine, fair enough.

If you seek to use this analysis to push a political agenda, then I am having trouble differentiating the morality between that and slave owners pointing to the shape of skulls based on race. Your explanation is an analogy, parasites dont grow up to eventually provide care for the host, it doesnt sound scientificially accurate to call a baby a parasite based on some of the characteristics. Further, calling a baby a parasite, or anyone for that matter, is an attempt to dehumanize them; dehumanization has been followed by violence in a number of horrific tragedies, but the violence is committed by people who find it justified, because whoever they are killing aren't really people.

you took the bate and missed the joke mon ami, and are now launching into unrelated screeds about slavery. you're not making things better.
you might be right, you should collect more data points, try this class of jokes out on more people and see how funny they find it, you could call women walking birth canals. It should be easy to formulate this comedy; take a broad category of people based on some immutable quality, like skin color, find the least charitable insult you could possibly imagine, like parasite, and see how funny they find it.
I'm ~60% sure they themselves are trying to bait someone, into an anti-abortion argument. They're definitely deliberately taking the most provocative stance possible, and trying to provoke more people along with them.

edit: re-reading their comments, I'm at least 80% sure.

They're making a cheeky reference to the fetus. Don't think too hard about it.
I didnt, and I knew the answer ahead of time. I think thats an insane way of thinking about things, barbaric and cruel, but I would rather parent spells it out and I leave it at that. Its the internet, people can and should say what they really think, im just helping parent get there.
I said exactly what I meant to say. I got there just fine on my own like the big boy I am.

I've had many a conversation with women that have decided to not have kids. This is where I first heard of a fetus referred to as a parasite. I found it quite humorous. It's their body after all*, and if that's how they think of having some life form growing inside their body, I'm here for it.

* as recognized in fewer places

Dont take it as derision. Id much rather a cultural exchange with you. I have many friends/family that are pro-choice, in conversation I have never gotten the impression that they would call an undesired baby a parasite, I would say thats rare.

I have a theory as to a clustering of ideas, you could call it a worldview, but its hard to pin down or narrowly define. However, some aspects appear axiomatic; and when you call a baby a parasite, that is an indication that you may share this worldview.

Id be interested in discussing it further. What are its fundamental predispositions, what do you have to assume is correct to adopt this view? What is the point of society?

I would be happy to exchange information on anarchocapitalism if you are interested.

That parasite gestating inside the female host.