Chimerism


#1

If life begins at conceptions, than a human embryo is life and has a soul, right?

Chimerism is a rare condition in which a mother is going to have twins, but the two embryos end up fusing together to form one. Thus, one child is born with two different sets of DNA (assuming the twins weren’t identical).

So my question is, does that one person now contain two souls? If not, what happened to the other soul? There was no death involved, just fusing of two embryos together.


#2

I think this goes to show that this concept of a soul is unnecessary and several centuries out of date.


#3

Actually, I think this more goes to show that the extreme exception does not define the norm.
Who knows what happens in this case. Since it is God that infuses the soul, I’m sure God would know what to do in a case like this.


#4

since I have studied the topic of chimerism in college i will respond.
The article i read studied the Marmoset monkeys who can become chimeric. It stated that they are not equal mixtures of two genetic individuals, but that they usually become chimeras when their placentas fuse.
As for humans, I would say that their is only one human soul present in chimerics because unspecialized stem cells are exchanged when the placentas are fused. But at the end of the day it is a freak occurrence in nature.


#5

But using that logic, couldn’t you say that an embryo does not have a soul?


#6

I don’t know. I would go along with what Dan-Man stated previously. After all, the super rare occurrence of chimerism is nothing like a normal embryo and should certainly not be used as an excuse to say that life does not begin at conception. That’s my:twocents:


#7

I guess the thing is that I don’t see there can be exceptions to the rule. If an embryo has a soul, then chimerism brings the very puzzling question of what happens to one of the souls. Once you start saying “well, this is a rare case and it doesn’t count,” then it brings into question the whole basis of the initial statement.

If the two embryos that form a chimerism have only one soul between the two, then can we really make the statement that an embryo has a soul? It would appear not because there are exceptions to the rule.

Please don’t think I’m being hostile; I’m just trying to understand how a documented biological case like this can be compatible with unofficial church teaching. (I say unofficial, because I don’t believe there is any place in church doctrine which states exactly when a soul is formed. Correct me if I’m wrong.)


#8

When one life process uses what were two bodies, the soul that was in one of the bodies leaves or stays. If it leaves, the two have two personalities and consciousnesses. These are conjoined twins. Some twins live a fairly long time sharing most vital organs and even part of the skull or neck. One mind controls some voluntary functions, the other the rest.
If one soul leaves, that is death. That infant goes where infants who die go. The remains are absorbed by the brother or sister and used.
So I don’t see an issue. If both live, both are souls. If one dies, but her or his organ tissues become part of a sibling’s body, well, that’s natural recycling at work. But the soul has gone away. You have just one soul there.


#9

But with chimerism, there are twins, meaning 2 separate embryos. If you were to completely separate them, they would grow up as two separate human beings. A chimera, which is not the same as conjoined twins, is when the two embryos fuse together to form one embryo, and then develop into one human being with two sets of DNA. There is no death involved.


#10

So these are originally fraternal twins, and completely, not partially, fused? Intriguing. I guess you definitely get one soul per consciousness and possibly an unconscious additional soul only God may ever know about.


#11

Correct, they are completely fused.

What you may be thinking about is more along the lines of a parasitic twin which is when a twin doesn’t fully separate leaving one considerably smaller and without development during gestation.


#12

If the final process is the formation of another embryo it could also mean the soul could be infused in this final formation after all God has no time limits and knows perfectly well the final formation. We cannot take away the sacred process in forming this final embryo.


#13

So let me ask a question to answer your question… Are you trying to argue that one of my twins (one survived, one died) didn’t have a soul? And if she did, where was it once she died? Of course she did and and when she died, I firmly believe her soul went directly up to heaven… so when 2 fuse and become one… wouldn’t the same or a similar thing occur?


#14

Well, if that were true it would mean that a soul doesn’t enter at conception.


#15

No.

And if she did, where was it once she died? Of course she did and and when she died, I firmly believe her soul went directly up to heaven… so when 2 fuse and become one… wouldn’t the same or a similar thing occur?

Perhaps you aren’t understanding chimerism. When the two embryos fuse together, there’s no death involved. It’s not as though one embryo dies and the other one ingests it. With chimerism, the two completely fuse together. Therefore, if you look at a chimera, they will have two different sets of DNA. Two living embryos become one embryo which grows into one human being.


#16

You know I have a theory that Chimera’s may be the possible missing piece of the puzzle when it somes to those suffering multiple personalities, hermaphrodites and transgenders. It certainly makes sense to me, because it is proven the twins that fuse together can be opposite genders.

Any body see that episode of House about Chimera’s? It was outstanding. It was about a little boy who kept getting threatened by an alien; turned out he was a Chimera, and his twin brother existed in his brain, and was pretty much psychotic, and was torturing him with this alien image.


#17

No. Chimerism is a freak genetic occurrence that has valid scientific underpinnings. Wikipedia (not my preferred source) states that there are only about 40 known cases of human chimerism.
I think the original poster is beating a dead horse on this one.


#18

If two bodies can become one, is it inconceivable that two souls can become one also?


#19

I am thinking on the lines of immaculate conception. Based on what is going to happen God in his wisdom had applied the merits of Christ to the birth of the Mother of our Lord. Much in the same way (except that here the attibution is for the future) there can be one soul which is attributed to this one embryo even though multiple embroys are going to be united to form this. If there were only one embryo then God has meant the soul for that but if the process involves multiple then all of them are essential for this one final embryo and hence the same soul is for all.

This is only speculation of course. I am keeping in mind the final formation of one enbryo from all and hence this line of thought.

Even if the soul has to be “fused” with embryo then when two had fused to form one embryo, then the soul must have been the same. I would not entertain multiple souls being fused but rather the same soul for multiple embryos (only keeping in mind that they are meant to be fused).


#20

No, that’s different. Hermaphrodism, (actually called intersexuality), has a number of causes, such as mosaicism. This can occur when an XY divides into an XY and an XO cell. Thus, as these two cells continue to divide, the XY will develop into male organs while the XO will develop into femaile.

[quote=kenmd]No. Chimerism is a freak genetic occurrence that has valid scientific underpinnings. Wikipedia (not my preferred source) states that there are only about 40 known cases of human chimerism.
[/quote]

Thanks for the stat. I actually would’ve thought it would be lower.

I think the original poster is beating a dead horse on this one.

People respond, so I respond back. Is that beating a dead horse? I find this to be a question with deep philosophical implications.


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