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Female-Only Reproduction In Mice


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Hiya Folks...Here's an interesting news story:

By MALCOLM RITTER, AP Science Writer

Just ahead of Mother's Day, scientists have found a way to cut dads out of the picture, at least among rodents: They have produced mice with two genetic moms — and no father. It is the first time the feat has been accomplished in mammals.

Scientists said the technique cannot be used on people, for reasons both technical and ethical. In fact, one of the mouse mothers was a mutant newborn, whose DNA had been altered to make it act like a male's contribution to an embryo.

But the new work sheds light on why people, mice and other mammals normally need a male's DNA for reproduction, and some experts say it also has implications for the idea of using stem cells to treat disease.

The feat is reported in Thursday's issue of the journal Nature by Tomohiro Kono of the Tokyo University of Agriculture in Japan, with colleagues there and in Korea.

They say they produced two mice, one of which grew to maturity and gave birth. Kono said this mouse, named Kaguya after a Japanese fairy tale character, appears healthy.

Some lizards and other animals reproduce with only maternal genes, but mammals do not.

Kono, in an e-mail, said the new technique might be useful with animals for agricultural and scientific purposes. When asked if he saw any reason to produce humans this way, he dismissed the question as "senseless."

Experts said ethical concerns and current technology would pose barriers to duplicating the technique in people. For one thing, scientists do not know how to create the precise DNA mutation in humans. Experts also noted that it took hundreds of eggs to produce just two mice and that the health risks are unknown.

However, the study provides new evidence for the standard explanation for why mammals normally need a male's DNA.

Scientists say that in an embryo, some mammal genes behave differently if inherited from the father rather than the mother, and that this paternal activity pattern is needed for normal development.

Relatively few genes act in that way, and they are said to be "imprinted." In some cases these genes are active only if inherited from the father, not the mother, and in other cases it is the other way around.

For the study described in Nature, the researchers got around the need for male-derived DNA by turning to mutant mice. The female mice were missing a chunk of DNA, and as a result, two of their genes would behave in an embryo as if they had come from a male.

What's more, the scientists took this mutated DNA from the egg cells of newborns, because at such a young age the DNA has not yet taken on the full "female" imprinting seen in mature eggs.

That DNA was combined with genes from ordinary female mice to make reconstructed eggs. Only two of 457 such eggs produced living mice.

Marisa Bartolomei, who studies imprinting at the University of Pennsylvania School of Medicine, said she was "stunned" that manipulating just the two genes removed the roadblock to producing live mice.

In fact, an array of other imprinted genes had also somehow taken on their normal levels of activity, as if there had been a standard fertilization. The researchers said they do not know how that happened.

Gerald Schatten, a stem cell researcher at the University of Pittsburgh School of Medicine, said the work shows that scientists need to thoroughly understand imprinting in human embryonic stem cells, which are recovered from early embryos. Otherwise, such cells might behave abnormally when used for treating diseases like diabetes or Parkinson's, he said.

Some scientists hope to produce human stem cells by stimulating unfertilized eggs.

Kent Vrana, a researcher at Pennsylvania State University who is studying the unfertilized-egg approach, said the Nature study is encouraging for that technology.

If a healthy, fertile mouse can be produced without a father's DNA, he said, that gives hope that stem cells from a similar process would behave normally.

http://story.news.yahoo.com/news?tmpl=stor...fatherless_mice

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aside from the whole animal rights issue this brings up for me concerning experimenting, ect....which i know some consider silly but thats off topic....aside from that....in all honesty i can't say the idea of female only reproduction is totally appalling to me. sounds far fetched and distant but in theory i am not sure it would be a bad idea for a multitude of reasons..

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:shock: :!:

Are these scientists the losers who sat at the back of the glass and giggled at the pictures in the reproduction section of the anatomy book? I'm trying to figure out why they'd be doing such testing. Is it because everything there is to be done...has been done?

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cijay, that was part of the whole thing that bothers me..... with using animals for this sort of experiment. why? its not like using mice for finding a cure for cancer or something.

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Why don't they use prisoners on death row for experimentation? The results would be more accurate. How can we trust mouse experimenting to be relevant to our own?

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underminethewalls

Hmm. It is a potential long-term solution to the fraying Y-chromosome.

The Y-chromosome is unravelling. It doesn't ever rejuvinate itself through mutation or by sharing genes with a partner Y as other chromosomes do, so each generation it gets progressively smaller. When it unravels enough, theoretically, its the end for us. Of course it would be millions of years in the future that this would happen, if we can make it that far to begin with.

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Silly Green Monkey

Can't use inmates, they've got rights and some are innocent. My friend thinks that males are an aberration, which will eventually become unnecessary. Don't forget that this experiment helped us understand more about imprinting.... I should bring the article to my Developmental teacher.

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Can't use inmates, they've got rights and some are innocent.

Unlike the mice who are guilty of.... :?:

Don't forget that this experiment helped us understand more about imprinting.... I should bring the article to my Developmental teacher.

I don't care what anyone calls it, it's fucking with genetics and appalling.

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Cate Perfect

I don't understand wasting the time and energy on learning how to make babies without men, when there are plenty of children got in the traditional way.

Cate

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Mice. Is there anything they can't do?
Scientists. Is there anything they won't do?

What about mousy scientists?

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PlatonicPimp

Geez, They're doing it because they are tryingto figure out an Ethical way to get stem cells for thier research, since they can't just go picking at the remains of aborted fetuses. It's not for the hell of it.

And As for the mice: They have never done anything that can be morally or ethically considered. Mice don't have intent, they aren't sapient. Saying the mice never did anything wrong is like saying an apple never did anything wrong. Neither has the capacity for moral or ethical behavior, they both are just what they are.

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But I just can't help thinking, have these scientists ever been a mouse? How do they know that animals have no intent or reason or compassion or desire or dreams? How do they know that animals can't feel?

It's like a tiger thinking, "It's okay if I kill this human. I mean, look at humans. They attack each other all the time; they're overcome with animalistic tendency. Obviously they can't feel if they do those kinds of things. So it doesn't matter if I kill him." How can these scientists prove that a tiger doesn't think these things, just because tigers have no voice boxes capable of producing speech? Human's innate mistake is to think that all creatures, if they do not act human, are therefore less than human. I've watched dogs experience jealousy and horses experience pain and ants cope with death. And all of them experience happiness and love. They all seem on a very equal level of intelligence to us.

I don't know... I just believe that any scientist who experiments on animals should watch them for a little while, and really watch. Animals display all the emotions that humans claim possession over. They just can't vocalize them, that's all.

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PlatonicPimp

I'm going into scientist mode. Think of it as devils advocate- I may not belive everything here, I'm just going about this logically

Engage Scientist mode.

Eh, what you are referring to is anthropomorhizing. You're projecting your own human feelings onto the animals. The animal itself may feel basic emotions, and they do make decisions, but its in much the same way a computer program analyze a situation and make decisions. Animals have instinct and a limited learning capaicity, but they do not have sapience. They aren't capable of Rationalizing, imagination or abstract thought, they are always focused on the concrete and immediate.

And scientist mode

Now, Dolphins are a often argued point, and apes are too. Rodents are pretty intelligent, and corvids are some damn smart birds. But intelligence and problem solving does not sapience make. Niether does the capacity to feel things. To my knowledge, only apes and dolphins have ever shown any capacity for abstract thought.

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ants cope with death

...?

Also...Platonic Pimp, is the word you're looking for "sentience"? There is a difference between possessing wisdom (as is implied in the word "sapient") and possessing conscious thought and perception. I thought perhaps you meant the latter.

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From the BBC Science/Nature section at http://news.bbc.co.uk/1/hi/sci/tech/3643847.stm

But as a result of this modification, just two out of 598 mice embryos made it to full term.

What use does this kind of research have at the moment? Why do 596 baby mice have to die for a useless escapade like this? There isn't a shortage of sexual men on this planet to keep the species going.

Why, why why???? :?

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As was previously mentioned, the idea isn't to eliminate men from the picture. The splicing apparently has something to do with stem-cell research. I'd prefer it to happen to embryonic mice than aborted fetuses, really. Stem-cell research is a rather important to modern medicine in its possibility for healing previously untreatable injuries, just as some kind of paralysis.

I don't really think of embryos as "babies" actually. They're mostly just stem cells in the embryonic period, having no recognizable shape.

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The "ants cope with death" was in reference to my observation of ants living in the kitchen of my campus housing. Two ants saw a crushed member of their colony, and spent ten minutes trying to pick the ant up to bring it back to their ant hill... or whatever is going on in the cracks of the kitchen... frankly, I don't want to know... but I've read that ants have graveyards (and really complex social structures; they're really interesting I think). Ants have civilizations comparable to humans...

but even if they're not intelligent it doesn't matter, I think. They're alive. So I guess I just can't see why scientists justify harming one creature in order to save another. It seems especially irresponsible to me to use intelligence to back it up. It shouldn't matter how intelligent species are. It should only matter that they were born on this planet, just as we were, and that therefore the planet belongs to nobody. I just don't understand why some people try to dominate it. This article reminds me of that...

I hereby step off my soapbox. :D

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Hmm. Somehow I can't believe that ants would just collect corpses and "bury" them. That's just unnecessary. From what I understand, ants collect their dead to be "recycled." In a Soylent Green, "the dearly departed is so much better with ketchup" kind of way. It's not what we would call coping with death. As charming as the image may be.

Ants do have complex systems of social interaction, stratified in a sort of caste system. And yes, they are alive. But, my feeling is that lots of things die so others may live. That's how the world works. It's why I'm not a vegetarian. Plants are alive, too. But we're heterotrophes, we can't internally produce our own food. So something's got to die if we want to live.

It's different with medicine, because it's not "natural," unlike predation. But still, I know I'd rather see a relative of mine be able to seek treatment for their injuries, thanks to experimentation with non-sentient beings, than know that a rat gets to live while my family member does not. It's a selfish way to be, I'll grant you that. But I can't help but value my loved ones' lives over that of some embryonic mice.

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But I can't help but value my loved ones' lives over that of some embryonic mice.

I agree. I would rather have hundreds of rats die so we can have a cure for cancer or AIDS than wonder "what if" when it comes to animal experimentation.

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sexiseverywhere

What about how some traits are sex liked, mostly to the x chromosome? How would that effect the occurence of sex linked diseases and such? This whole thing's pretty creepy to me...

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Cate Perfect

It is a little...Gattaca.

(Hi, sie. *waves*)

Cate

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