Lesbian Parents

Factual Questions
1

A lesbian couple who are friends of mine want to have a child. However, they don’t want the usual route of finding a male donor to impregnate one of the couple and then raising the child as theirs. They want to both be genetically parents of the child.

I’ve searched on the internet, but I can’t find any info about this topic.

Is it possible to combine the eggs of two women to create a zygote? (Unfortunately, in this case, one of the pair has had a complete hysterectomy.)

Or, can the genetic info of one of the ladies be extracted and injected into a sperm whose genetic material has been removed, then this sperm used to fertilize the egg of the other woman?

2

-Ok one of the partners has had a complete hysterectomy, and she still wants to have her DNA impregnated into the sperm of the Donor?? :confused:

-UHHHH…NO…I do not think that is scientifically possible…

-I completely understand her point of view and her want to be a genetic link to the child, but I do not think that is physiologically possible. Genetically, possible for that matter. I am not a doctor, but a rather lengthy google search has yeilded nothing.

-I do not want to be pessimistic here and would love to be proved wrong, but I do not think the scenerio expressed in the OP is possible. It will be interesting to see if another poster has a different take.

3

Does the one that had the hysterectomy have a brother that could be a donor? That’s the closest I can think to what they want.

4

Bad news, chum.

If one of them has had a complete hysterectomy, she’s got no eggs to use. Unless she had the foresight to have some saved, somehow, when they did the surgery.

As far as I’ve seen, current tech & know how isn’t quite up to this task yet. Even if it were, this sort of tampering with human subjects would probably be considered “unethical” by current prevailing standards.

IANA doctor nor biologist nor geneticist nor expert of any kind of this subject. Maybe one will happen along to answer your question better than I. :wink:

5

Dang but you people are fast!

That’s a good thought about the brother, though. That probably is the closest they can get. Can’t remember the numbers, but it’s a pretty close similarity.

6

Just for the sake of argument, suppose they both had eggs. There’s still the iffy step of combining two eggs to make a zygote. Is this even theoretically possible? I realize the product would be correctly diploid, but it’s probably more complicated that that.

7

I think if both partners still had the full reproductive system, it’s theroretically POSSIBLE…don’t know if it’s been done, though. But as folks above have mentioned, full hysterectomy means you don’t have eggs.

I suppose, if you went really sci-fi, you could extract DNA from the other woman’s bodily fluids to insert in the egg of the other woman. Don’t know whether science is up to that yet. On the related note of reporductive science, here’s a link from the Washington Blade, DC’s gay & lesbian newspaper (might only be valid through tomorrow, since it comes out on Fridays):

http://www.washblade.com (go to health news and check out the article on artificial sperm)

8

Well, let’s see…ignoring the limitations of current state of the relevant technological arts and focusing only on the biological logistics…

Meiosis, the process by which ova are created, is different yet similar to mitosis, the ordinary process by which somatic cells duplicate. In mitosis, the chromosomes–which already exist as pairs–double, the pairs of pairs separate and polarize to opposite sides, and then the cell membrane divides, so you end up with two cells each with a full component of paired chromosomes. In meiosis, IIRC (been a while since 7th grade bio), the proto-cells start off with the normal set of paired chromosomes; they double and polarize and split once, but not equitably: one of the two “daughter” cells gets all the gelatinous goodies and whatnot, the other is a “throwaway” called a “polar body” that contains very little except the nucleus and its chromosomes.

Then both of these split a second time, but this time without duplicating: the pairs SPLIT, the cells divide, and the final four cells are all haploid, containing only half the genetic material of a conventional somatic cell. Oh, and once again only one of the two “daughters” of the cell that started off with all the goodies ends up with all the goodies, so you have three polar bodies and one ovum that contains all the good stuff for furnishing a fertilized ovum with the stuff it needs to become a blastocyte.

So, of our two lesbians, she of the previous hysterectomy cannot give birth, and if it was a complete radical hysterectomy (i.e., no ovaries), no ova or polar bodies either, but she still has somatic cells, so the equivalent of a polar body could be created by snipping all her pairs randomly in half. The resulting genetic content is equivalent to that of sperm (no possibility of a Y in there of course). So once we’ve snipped out half the pairs, creating an artificial polar body, we insert it into the other lesbian’s ovum, subjecting it also to whatever chemical prompts are normally applied by the presence of spermatozoa so as to kick it into “oh yeah I’m pregnant” mode. Then it gets implanted into Lesbian II’s uterus.

In other words, if the technology can handle it, the basic biological components are there and would come from the two women involved.

9

Nice post, AHunter3.

In response to the OP:

  1. Yes, as AHunter3 has explained, it is theoretically possible. Probably quite difficult, though, to get a haploid chromosome number from a somatic cell, as would be required in this case.

  2. However, we are not that close to it having the biotechnology to make this happen. This goes several steps beyond cloning an adult human, and no one has done that yet (as far as we know). However, I would not rule out something like this being possible in 10 years or so. On the other hand this is not likely to be an active field of research in animals, because straight cloning is more useful and easier; nor in humans, because of ethical considerations.

10

Actually Homebrew, there is some hope for your friends!

When I read your OP I remembered reading an article a while back about some Australian researchers that had experienced a certain degree of success fertilizing the eggs of mice without using sperm or without using the reproductive material of another female mouse. I found a link to a story here, it is not the story I remember reading, but the general idea is still there. I’ll see if I can find the article I read, it was much more informative.

This type of technology is years from fruition. It’s very complex, fraught with snags and there’s unending ethical questions, but who knows? There’s still hope.

Personally, as soon as they figure this stuff out, I hope your friends are at the front of the line. :slight_smile:

11

I’ll be jiggered if I can find that darn article I remember. But if your interested in reading more you can click here or here or here.

12

I am a geneticist, and work closely with a lab involved in some of these issues. So:

Aside from the fact that one of these women doesn’t have ova, imprinting is your major problem here. The haploid DNA that come from sperm and the haploid DNA that comes from eggs are each imprinted, or “marked” differently. The developing embryo only uses some genes from the maternal genome, others from the paternal genome. Embryos which are artificially created (yes, it’s been tryed in a variety of organisms) using two maternal haploid genomes ends up just being a mess of disorganized tissues - bone, hair, skin, etc… This also happens naturally in the ovary sometimes, and it is called a dermal cyst (not the same as an ovarian cyst). Embryos created from two paternal genomes create extrememly aggressive cancer-like embryos which do not form fetal structures, but try and take over the mother’s bloodstream. They’re very dangerous.

Cloning from a single adult has been shown in a number of species, and there’s really no scientific reason that it shouldn’t work in humans (ethics aside). This is presumably because the cells in your body maintain the “marking” of the maternal and paternal alleles, and so provide the activated egg with both genomes necessary. (Note: during the development of the egg/sperm, the imprinting of the genome is removed and reprogrammed. This means that even if you are female and a particular chromosome was inherited from your father, if you pass it on through your ovum, it will now be marked as “maternal”. Get it?)

However, there is currently no technology to take adult somatic cells (not ova) and fuse them in any way that would create anything useful for reproduction. And there is currently no way to reprogram ova into having a paternal imprinting pattern, so even two women with functional eggs can’t reproduce together. I don’t have any idea if that will still be the case in ten years.

I hope this post made any sense at all.

mischievous

13

I would take an egg from one woman & artifically inseminate it & then put it in the other woman to grow. That would be fun.

Its not possible of course with someone with a complete hysterectomy, of course.

14

Is this similar to what Cecil was talking about in this column?

15

heard about this on leno last night, but didn’t find too much on the web. artificial sperm is now being tested in mice. i guess they use chemicals to make the chromosomes duplicate themselves, therefore there is no need for sperm and every resulting birth would be female. i know the OP says BOTH want to be genetically involved, but this is still related, and a step in the right direction.

16

I saw an episode of NOVA which discussed various forms of IVF. One of the methods they mentioned was called “cytoplasmic transfer” in which the non-nuclear parts of one womans egg is transfered to the egg of another which is them artificially inseminated. Since the cytoplasm contains mitocondrial DNA from the donor, the resulting baby will have DNA from both women (and the sperm donor of course).

This may not work for the women in the OP since due to the hysterectomy issue, but it’s interesting none the less.

17

Piper, that’s exactly right. There is a fine line between teratomas (germ cells which have become cancerous) and dermal cysts (ova which have spontaneously activated themselves). It’s not always possible to tell the difference, especially if you’re not willing to pay for some very expensive tests. Both are virtually always benign, so it hardly matters from a personal standpoint.

I had a dermal cyst about a year ago that grew to be 7.5cm in diameter before anyone noticed it. Unfortunately, I noticed it when the weight twisted the ovary around and cut off the ovary’s blood supply. Painful doesn’t begin to describe it. I lost that ovary, but the cyst itself was benign.

Minkman cytoplasmic transfer is possible, and the mitochondria could be taken from non-egg cell of the hystrectomized (real word?) woman, but mitochodrial DNA is such a vanishly small percentage of a human’s total DNA that it would hardly matter. Except perhaps, emotionally. Also, the few genes in mitochondria all affect basic energy processing and are functionally identical in most humans. They have no effect on development, looks, personality, height, skin color, or any of the many other traits that most people want their children to resemble them in.

jonfromdenver. I’ve never heard of artificial sperm. See, the technology is always advancing. I imagine it will be a while before they actually work, though.

mischievous