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efreysson
04-17-2016, 05:48 PM
I'm writing about a lesbian couple having a child in a sci-fi future story, and I was wondering how fertilisation and DNA work. I thought that maybe, with future technology, one woman could have an egg fertilized with the DNA of another, letting that one serve as the genetic father.

I was also kind of wondering whether there's any biological reason why a woman shouldn't give birth to her own clone.

Could someone help me out here? I'm sure I'm getting some terminology wrong here.

Dennis E. Taylor
04-17-2016, 06:26 PM
Reproductive scientists create mice from 2 fathers (http://phys.org/news/2010-12-reproductive-scientists-mice-fathers.html)

The described technique could, in principle, work for females. The only issue, of course, would be that your characters couldn't have a son.

As to the clone question, no reason that I can think of.

efreysson
04-17-2016, 06:30 PM
Reproductive scientists create mice from 2 fathers (http://phys.org/news/2010-12-reproductive-scientists-mice-fathers.html)

The described technique could, in principle, work for females. The only issue, of course, would be that your characters couldn't have a son.


Ah, of course. No Y chromosome. Hmm, I was going to have one daughter and one son. I'll have to do some rethinks.

Thanks.

King Neptune
04-17-2016, 06:46 PM
Ah, of course. No Y chromosome. Hmm, I was going to have one daughter and one son. I'll have to do some rethinks.

Thanks.

With a little gene transplantation that would be easy. Just remove one X and replace with one Y from a donor. Gene editing is being done now.

http://genetics.thetech.org/editing-our-dna-molecular-scissors
http://www.bbc.com/news/health-36049907

TellMeAStory
04-18-2016, 01:45 AM
efreysson, there's more than just DNA involved. You've got to deal with methylation as well--that is, if you want to be annoyingly scientific about it.

Check out http://genetics.thetech.org/ask-a-geneticist/imprinting.

For fiction, the bar might be lower

kuwisdelu
04-18-2016, 01:54 AM
There has been promising research in creating sperm and eggs from stem cells. (http://www.nature.com/news/rudimentary-egg-and-sperm-cells-made-from-stem-cells-1.16636)


I'm writing about a lesbian couple having a child in a sci-fi future story, and I was wondering how fertilisation and DNA work. I thought that maybe, with future technology, one woman could have an egg fertilized with the DNA of another, letting that one serve as the genetic father.

Just to point out... you probably don't want to call a woman "the genetic father".

She's a woman. Even if her genetic contribution is sperm, she would still be a mother.

Edit: Speaking of which, if you just want a lesbian couple with genetic children, then one of the partners could be transgender. No future tech necessary.

Roxxsmom
04-18-2016, 02:08 AM
There has been promising research in creating sperm and eggs from stem cells. (http://www.nature.com/news/rudimentary-egg-and-sperm-cells-made-from-stem-cells-1.16636)



Just to point out... you probably don't want to call a woman "the genetic father".

She's a woman. Even if her genetic contribution is sperm, she would still be a mother.

Depends on whether you're going with the biological or sociological definition of "father." Given the disconnect between the two (biologists define the father as the one who produces the sperm, since the role male animals play in nurturing young ranges from being completely absent to carrying the young and birthing them, like seahorses do), and the loadedness of the word father and mother in a sociological sense, it might be better to come up with completely new words.

On the other hand, if both parents identify as female, and they both want to be called mothers, it seems appropriate to call them both mothers.

Egg mother and sperm mother? That will twist some knickers.

kuwisdelu
04-18-2016, 02:13 AM
On the other hand, if both parents identify as female, and they both want to be called mothers, it seems appropriate to call them both mothers.

I'm sure exceptions exist, but I doubt many female parents would want to be called "father" instead of "mother" socially just to satisfy pedantic biologists. I sure wouldn't.

Latina Bunny
04-18-2016, 02:37 AM
Yeah, I would think they would need a new term for the women who don't want to be called "fathers"...

I thought I heard about a rat dna experiment involving two female rats a long time ago?

kuwisdelu
04-18-2016, 02:40 AM
Yeah, I would think they would need a new term for the women who don't want to be called "fathers"...

IMO, "mother" works just fine. No need for a new term. Plenty of kids have two moms. ;) :)

CL Polk
04-18-2016, 02:40 AM
you could ask the lesbian couples with children that you know what their kids call them...

Helix
04-18-2016, 02:44 AM
Reproductive scientists create mice from 2 fathers (http://phys.org/news/2010-12-reproductive-scientists-mice-fathers.html)

The described technique could, in principle, work for females. The only issue, of course, would be that your characters couldn't have a son.

As to the clone question, no reason that I can think of.


Two fathers and a mother. The ovum had to come from somewhere. And the uterus.

Offspring from two mothers (http://news.nationalgeographic.com/news/2004/04/0421_040421_whoneedsmales.html) happened long before they bothered to try it with males (and a female, see above).

As for cloning, yes, it's possible with humans in principle. Definitely possible with some non-human animals: don't forget Dolly the Sheep!

And bioengineering males shouldn't be that difficult in a SF setting. Only a small number of genes on Y are relevant to sex determination.

Latina Bunny
04-18-2016, 03:20 AM
IMO, "mother" works just fine. No need for a new term. Plenty of kids have two moms. ;) :)

Yes, ok, but there are some families that have different names/nicknames when addressing the two moms. (Unless you want to call them, Mom 1 and Mom 2...)

kuwisdelu
04-18-2016, 04:26 AM
Yes, ok, but there are some families that have different names/nicknames when addressing the two moms. (Unless you want to call them, Mom 1 and Mom 2...)

Oh, yeah. By "new term" I thought you meant like, some scientific medical-sounding neologism specifically for sperm-donating female parents, not like "Mother" vs "Mom" vs "Mami Bunny". :)

Katharine Tree
04-18-2016, 04:34 AM
As far as a woman's own DNA standing in for the DNA from a partner: this would present the same problems inbreeding presents, specifically, if a woman is a carrier of a genetic disease, and her offspring ends up with two copies of that allele, the offspring will have the disease. And genetic diseases are usually problematic.

This can be solved if your process is fine-grained enough to pick up on which alleles are being passed on, and to make sure that the offspring doesn't get a double dose of any problematic ones.

Latina Bunny
04-18-2016, 06:58 AM
Oh, yeah. By "new term" I thought you meant like, some scientific medical-sounding neologism specifically for sperm-donating female parents, not like "Mother" vs "Mom" vs "Mami Bunny". :)

Lol, I misunderstood. Sorry, heh. :P

Yes, like what you said! (Lol, si, Mami Bunny! :3 ) The terms of endearment, I guess they could be called? I would think that some moms would like to make up or choose new terms of endearment or slang terms in such a future with this tech, or something.

Sounds weird, but it seems that humans are always making up slang or reclaiming old terms and stuff, lol. :)

frimble3
04-18-2016, 07:16 AM
We're always doing it in this context, even - step-parents, multiple step-grandparents, etc., as well as the 'two mommies' situation.
I've heard older women arguing as to what diminutive of 'grandmother' they wanted to be called, and what they definitely wouldn't stand for (right up to the moment the new grandbaby used it and would not be deterred). ;)
I could see a general term referring not to who donated what (this sounds like something you'd only bring up when making a criticism of the child: 'she gets that from your side, doesn't she?'), but who carried the pregnancy, was visibly pregnant. 'Womb mother'?

frimble3
04-18-2016, 07:27 AM
I remember reading a short story, long time back, about a newly colonized planet where some disease/condition killed off all the males. The female survivors used some kind of egg-mixing for parthogenetic reproduction. Story wasn't about that, it was about what happened a generation or so later when men 'found' the Lost Colony, so I don't recall much about the details.

kuwisdelu
04-18-2016, 07:36 AM
who carried the pregnancy, was visibly pregnant. 'Womb mother'?

It's not terribly sexy, but I've heard midwives use "gestational parent" and "non-gestational parent", which both work regardless of which parents are male or female or neither or both.

Roxxsmom
04-18-2016, 07:46 AM
I'm writing about a lesbian couple having a child in a sci-fi future story, and I was wondering how fertilisation and DNA work. I thought that maybe, with future technology, one woman could have an egg fertilized with the DNA of another, letting that one serve as the genetic father.

I think it's plausible that we could have technology that allows two eggs to be merged, or the DNA from an egg inserted into a sperm that has had its DNA removed. That doesn't sound that different from what's being done now with cloning.


I was also kind of wondering whether there's any biological reason why a woman shouldn't give birth to her own clone.

Could someone help me out here? I'm sure I'm getting some terminology wrong here.

I can't think of a reason why it would be a problem. As I understand it, scientists still haven't been successful at using the type of cloning techniques that gave us Dolly the sheep and countless other cloned animals to our closest relatives (http://www.livescience.com/32083-cloning-people-biology.html) (I think they've maybe cloned monkeys but not chimps or gorillas or humans), but there's an interest in doing so for the purposes of creating embryonic stem cells at least. There's no reason why a method might not be found to allow human cloning eventually (even soon), and a gene mother could certainly be the gestational mother of her own clone.

The ethics of reproductively cloning humans, should the technology become available, is under fierce debate, but I suspect that once it becomes possible, someone will do it.

Latina Bunny
04-18-2016, 08:16 AM
'Womb mother'?

Lol, so alien-sounding. I like it. I shall use it as a typical parental guilt trip or threat. "I'm your womb mother, Johnny. I brought you into this world; I can take you out." Perfect. :3

(ETA: Kuwi's "gestational" terms work for me, too, as a generic medical/scientific term. I kind of like the feminine look of "Womb Mother". Sounds like some badass alien queen mother or something, lol. Feel "Mother Earth-y", to me. I don't know why, and maybe it sounds weird or gross to some people, but I kind of like it. XD )

eskay
04-18-2016, 08:42 AM
Yes, all of those situations are completely plausible in a sci fi scenario, even in a near-future setting. Engineering a Y chromosome from scratch (like Helix said, only a few genes on the Y chromosome are necessary for sex determination), or adding one from a donor, also seems totally reasonable. Fun(?) Y chromosome fact: some otherwise healthy men lose some copies of their Y chromosome as they age. It's possible that this results in a slightly higher risk of some types of cancer, e.g. from smoking.

In terms of genetic disease, you wouldn't have to worry about that with a mother carrying a clone: the daughter would have exactly the same genome. Issues might occur if you used the same genome to produce both egg and sperm, and created a zygote from fertilization. In that case, the mother's genes that were inherited from her parents would recombine, and it's possible that the child could and up with two copies of a grandparent's allele. If that allele is recessive, having two copies would be enough to cause genetic disease when one copy did not. In terms of incompatibilities with carrying the child, I can't think of any--that type of thing mostly happens because of differences between the mother and the child. (but, I'm not an MD)

One other possible idea if you wanted one of the children to be male: one of the mothers could have an XX/XY chimeric condition, in which a fraction (could be small!) of her cells could have an XY genotype. This could result in an intersex condition, but not necessarily. In the absence of routine genetic sequencing of individuals at birth (which might in itself be a bit of a plot hole, depending on the setting...) it could have gone undiagnosed until the parents decided to have a baby.

kuwisdelu
04-18-2016, 09:05 AM
One other possible idea if you wanted one of the children to be male: one of the mothers could have an XX/XY chimeric condition, in which a fraction (could be small!) of her cells could have an XY genotype. This could result in an intersex condition, but not necessarily. In the absence of routine genetic sequencing of individuals at birth (which might in itself be a bit of a plot hole, depending on the setting...) it could have gone undiagnosed until the parents decided to have a baby.

Indeed. There are various ways one of the mothers could have a XY genotype. As I mentioned earlier, one mother could be transgender, or have an intersex condition like Complete Androgen Insensitivity Syndrome (CAIS).

efreysson
04-18-2016, 12:55 PM
efreysson, there's more than just DNA involved. You've got to deal with methylation as well--that is, if you want to be annoyingly scientific about it.

Check out http://genetics.thetech.org/ask-a-geneticist/imprinting.

For fiction, the bar might be lower

Well, yeah. I'm not going to go into the scientific details. The protagonist is the teenage daughter resulting from the two moms. I just wanted to hear if it's possible.




Just to point out... you probably don't want to call a woman "the genetic father".



I'm sure exceptions exist, but I doubt many female parents would want to be called "father" instead of "mother" socially just to satisfy pedantic biologists. I sure wouldn't.

Yes yes, I was just getting across what I have in mind, on the gene-thing. I don't have the science vocabulary.

For terms, I'm thinking maybe "mother and birth-mother".

Latina Bunny
04-18-2016, 02:26 PM
For terms, I'm thinking maybe "mother and birth-mother".

For me, I personally like those terms as well. :) I have used such terms in my own writing as well.

I really feel that there still needs to be some sort of terminology for the gestational parent, so those terms would work for me.

(I feel, in my heart and gut, that this is an important detail to know. I would want to know who "birthed" me.)

However, I know other people feel differently, and some may not like gendered terminology, either. It really comes down to personal preferences and cultural beliefs, I feel.

It's really up to you. It's your scifi world and your characters. :) Have fun writing! :)

WeaselFire
04-19-2016, 08:58 PM
Well, yeah. I'm not going to go into the scientific details. The protagonist is the teenage daughter resulting from the two moms. I just wanted to hear if it's possible.

It's science fiction. Possible doesn't matter, only that it's plausible.

Jeff

autumnleaf
04-21-2016, 07:03 PM
It's science fiction. Possible doesn't matter, only that it's plausible.


And the OP's situation sounds plausible to me with future technology. I've certainly read weirder things in terms of genetic manipulation without my disbelief losing suspension. (See Seveneves by Neal Stephenson for a recent example)

morngnstar
04-21-2016, 07:36 PM
'Womb mother'?

"Birth mother" is a term I've heard to distinguish from either the "biological mother" in the case of egg donation or surrogacy, or from the "adopted mother". It's potentially possible one person could have all three.

In this case you would have one birth mother and two biological mothers. The trickiest part is what to call the mother who isn't the birth mother. Biological mother doesn't distinguish her in this case. I can only think of "non-birth mother", but who wants to be called "non" something? I guess this is not a new problem, because there are lesbian couples in which one mother is both the birth and biological mother through artificial insemination. My guess is it doesn't actually come up that much. They're just both mothers. After the birth, how often is it important who was the birth mother?

autumnleaf
04-22-2016, 02:28 PM
With current technology it is possible to have one woman donate the egg and another carry the baby, although you still need a genetic father to provide the sperm. It is more complicated than simple AI: the egg donor has to take massive amounts of hormones to produce multiple eggs and then get them extracted by pipette, and then the prospective pregnant woman would also take hormones to get her body ready for the embryo which would be transferred to her uterus in another procedure. Essentially it's IVF but with two different women. Most lesbian couples would opt for AI as the less expensive and less physically draining option.

(This is probably not relevant for the original question, where the birth took place a long way before the story and the technology would be different.)