Semi-Identical Twins Discovered 224
daftna writes in with a story from Nature about a pair of twins who are neither identical nor fraternal: they are semi-identical. Researchers discovered twins who share all of their mother's DNA but only half of their father's. Both children are chimeras — their cells are not genetically uniform, but include a mix of genes from two separate sperm cells that fertilized a single egg. This is, apparently, not as rare as one might think; but the resulting fetus is rarely viable. This report marks the first known incidence of two half-identical twins resulting from a double fertilization.
Sounds like mom was a busy girl. (Score:5, Funny)
Re:Sounds like mom was a busy girl. (Score:5, Funny)
No problem (Score:5, Funny)
No I can count up to five, even with one hand busy!
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Re:Sounds like mom was a busy girl. (Score:5, Funny)
Re:Sounds like mom was a busy girl. (Score:5, Interesting)
Re:Sounds like mom was a busy girl. (Score:5, Interesting)
doesn't sound like a big deal (Score:2, Insightful)
I dunno about you, but when I go to the restroom, people usually don't see my weenie. And there's always the stalls to do your business, you know. Furthermore, if people really want this sort of thing "corrected", there are surgical procedures and drugs to make anyone clearly male or clearly female. As for medical risks, most people who are chimeras never seem to find out anyway.
On intersexuality (Score:5, Insightful)
Do you really think that this is the biggest problem intersexual people will ever face in their life? If yes, you seriously need to read up on these things a bit.
First of all, as a disclaimer, I'm not intersexual myself, but I'm interested in inter- and transsexuality and know a couple of people who are. Most of the intersexuals I know had a gender surgically assigned to them after birth, too (female, FWIW; as doctors say, "it's easier to dig a hole than build a pole"). But you know what? Neither of them is happy.
In fact, the *exact opposite* is true. *Every single* intersexual I've talked to or heard about has said the same thing so far - that doing so is, essentially, butchering, a traumatic experience that will haunt you for your entire life. Even in these times where sexual reassignmet surgery is not impossible anymore, the results are far inferior to anything that nature came up with (if you can even afford the whole procedure!), and the psychological problems associated with having your body mutilated after birth are just as serious.
What really needs to be done when an intersexual child is born is really easy: bloody leave them alone. The child will eventually grow up and be able to make their own decisions; if they decide then that they really belong to one gender, it's not too late to do surgery etc.. What's more, it might well be that the child decides that they're really male - contrary to popular opinion, "intersexual" and "transsexual" do not mean "a guy who wants to become a chick".
But there's also a decent chance that the child will say "I'm happy the way I am", and who's to say that that's not within their rights? If the only reason you can come up with is that there might be confusion over which restroom is appropriate, well... I'm sorry, but that isn't quite enough.
What's more, when you're talking about things like restroom usage, you make a very fundamental mistake: you look at what other people and society in general will see the child as, rather than what the child themselves thinks. But it's the child who will have to live with their body; the idea that society has a right to say "you don't fit into our binary system, so we'll cut up your body and then pretend that you do (even though you really still don't)" is outrageous.
FWIW, BTW, another fundamental mistake that's often being made is the assumption that it's even possible to reassign gender - that is, the actual gender that someone identifies as, as opposed to their physical sex. One of the reasons why intersexual people were mutilated in the past and raised as girls is that doctors (wrongly) believed that if you just cut off everything that was non-girly and if you just put the child into a dress and told them they were female, they'd really believe it and grow up as a normal, well-adjusted *woman* - but in reality, it doesn't work, and never has.
Of course, I do understand that there are no ulterior motives - doctors, parents etc. really are trying to help intersexual children. But it's also important to realise that it's not working and that the only thing you're doing is CAUSING harm, not preventing it.
So, although this has little do to anymore with the original TFA, just let me say this: leave intersexual children alone, and let them make their own decisions when they're old enough. Until then, be tolerant, be honest, explain to them why they're different, and explain that it doesn't make them worth less or anything like that. That's the ONLY way you can actually help them.
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You mean like watching bizzar porn hu?
Pervert...
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I have no idea what you're talking about.
- Pat
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I think that victims should not be haunted or troubled about the way that they have been reassigned. There's a lot of angst about it - but there's also a lot of evidence that sexuality, including the ability to reach climax, and the quality of the climax, is largely psychological. True - the damage to (or removal of) tissue with large amounts of nerve endings can be crippling. And the longings that one has for part
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I'm completely normal (physiologically) - one might say "average".
And I wasn't happy about the locker-room situation either.
In fact, my son doesn't like that either.
The truth is, we have a very sick society. It's harder on some (like you) than others. It's a damn shame that medical "science" hasn't figured out what to do about a significant and naturally-occurring percentage of our human biology, and instead, still clings to th
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Those of us who have experienced the hatred, the violence, the rape, the cigarette burns.... the usual stuff every transsexual boy or girl goes through should be kinder to those who are Intersexed. Remember, this woman was made transsexual at the point of a scalpel.
I'm both Transsexed (as in "brain physically mainly of one sex, body physically of the opposite sex:"), and Intersexed. Androgen Insensitivity, Adrenal Hyperplasia, and a Leydig cell anomaly, not that I have any Leydig cells any more. I know wha
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Probably the different father would pay.
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I can't seem to get this outta my head...
"So who da baby daddy?"
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I remember reading a long time ago, in one of the Wallace/Wallechinski Book Of Lists, an article about a case in the seventies in Germany, more mundane in that two eggs were fertilized, so that the kids were not chimeras, but extremely weird in outcome, as the woman gave birth to two boys, one fully african and the other fully caucasian!
I believe it's the only recorded case of two simultaneous fertilizations from different ethnic gene pools, but
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Surely the boys must have been either half african and fully caucasian, fully african and half caucasian, or half african and half caucasian.
JP
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Discovery Health "I'm my own twin" (Score:5, Interesting)
Re:Discovery Health "I'm my own twin" (Score:5, Interesting)
Re:Discovery Health "I'm my own twin" (Score:5, Funny)
That could be of Biblical proportions.
Already happened. (Score:5, Informative)
http://news.bbc.co.uk/2/hi/science/nature/6196225
Re:Discovery Health "I'm my own twin" (Score:5, Informative)
As we probably all know 'virgin' was indisputably a mistranslation; the Hebrew for 'young woman' (almah) was translated into the Greek for 'virgin' (parthenos). I wonder why we all still refer to her as the virgin Mary, now that we know she wasn't (necessarily, to be absolutely pedantic) a virgin.
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Re:Discovery Health "I'm my own twin" (Score:5, Informative)
The issue is not with the New Testament; there is no question that Mary is reported to have been a virgin in the New Testament. The issue originates with the Septuagint, the Greek translation of the Old Testament produced by Jews before the time of Christ, and it has to do with the translation of Isaiah 7:14, an ostensibly Messianic prophecy. (The Septuagint was the translation used by New Testament writers.) It translates the Hebrew "almah" with the Greek "parthenos". Parthenos almost always means "virgin", while almah has a slightly different but overlapping semantic range. It's closer to "maid, unmarried girl, young woman of marriageable age". (Your "young woman" leaves out the unmarried/of marriable age implications.) Culturally speaking, an almah most likely would be a virgin--that would be the strong expectation, and it's enough to make "virgin" a connotation of "almah". While parthenos is not a precise translation, it is not a mistranslation. At the very least, not indisputably so. My goodness, man, just read the Wikipedia entry on almah and follow the references! This is not obscure information.
Sure, if you limit the meaning of "almah" to "young woman", it makes for a better game of "Hee hee, look at the silly Christians," but if you're interested in honest scholarship, you'll have to open your mind a bit.
Re:Discovery Health "I'm my own twin" (Score:5, Insightful)
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I like the old testament though, it's cool the way archaeologists went round the world, bible in hand, and found all kinds of 'mythical' places were real. Mind you, I read it as a very old book, not as a guide to life or any such crap. Tried to read it in the Hebrew once, but I wasn't patient enough to learn all of the language.
The new testaments a crock, it reads like a comic book.
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Doesn't have to me a mis-translation (Score:3, Interesting)
Then there are things like an elastic hymen, and various other fun ways to end up pregnant while technically a virgin.
And to make it even more fun, think this: they later had to invent an explanation for exactly this kind of thing, namely the succubi and incubi. Virgin virtuous girls (yeah right) were
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Only if your boyfriend has a working set of ovaries, womb, and vagina. Note that it's a bit like the WoW equipment sets too: you need all pieces to get the big bonus. Just two out of three isn't going to do the trick.
Also that's assuming that you are a man. Fucking someone up the ass with a dildo or strap-on, sadly, misses another piece of the equation, namely the sperm. I'm affraid you can't quite get the synergy effect without that part.
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I didn't say "rape" (Score:2)
And a lot do say "yes" at some point or another. I was reading a statistic about a decade ago, and IIRC about 50% of the polled women had taken it up that route in the USA, and it was raising well over 80% in
Sorta yes and no (Score:2)
1. Even if it was invented later, still, at some point people -- and for that matter the church sponsoring those inquisition trials -- had to believe or preach _both_ at the same time. Both that (A) Marry's virgin pregnancy was a one-time divine-intervention-only miracle, and (B) that the same was possible via incubus, and happened all the time.
2. Believe it or not, incubi and succubi aren't an inqusition-only thing. Belief in that kind of thing is spread all over the world, including in are
basically, yes (Score:2)
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Of course it would really be good to be able to prove Mary was no virgin, because religion, as it is right now, causes more problems than it solves, but we have to be fair with the historical texts and recognize the fact that people were not so "accurate" back then.
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Did nobody tell you to be careful when, uh, fooling around?
Link? That sounds pretty incredible. (Score:3, Insightful)
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Some of these women nearly lost their kids because they couldn't prove via DNA tests that the kids were theirs - child services thought they'd switched them at the hospital or something, even though the father was the father.
Re:Discovery Health "I'm my own twin" (Score:5, Informative)
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Re:Discovery Health "I'm my own twin" (Score:4, Informative)
More importantly, if you call a person who is intersex a hermaphrodite many will likely be quite unhappy with you. Its akin to calling a Native American an 'Indian' - not only generally disliked by the people you are labeling but also factually incorrect because of a misunderstanding of what the term means (or on what continent you are located.)
Nick
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Its akin to calling a Native American an 'Indian' - not only generally disliked by the people you are labeling but also factually incorrect because of a misunderstanding of what the term means (or on what continent you are located.)
Not really. Most Indians call themselves Indian or whatever specific tribe they belong to. Indian is likely a result of Columbus referring to them as In Dios - I'm pretty sure India as a country didn't quite exist at the time, and it's not that hard to figure out whether you
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That's not necessarily true insofar as that some intersexual people (whether they're true hermaphrodites or not) actually use the term "hermaphrodite" as a lab
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When she was DNA tested to receive welfare, the DNA indicated that her children weren't hers - but the mother would've been someone with similar DNA *like a brother* of hers.
Somehow you took that to mean that she had hermaphroditism, which would have made her infertile. That's pretty illogical - how the hell does a person have male
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Unfortunately there's still so little research done on the more outrageously rare (we think) Intersex conditions, often because of sheer emberressment. Think how terrible it must be to be a self-fertilising hermaphrodite. Or to be a really spectacularly gorgeous-looking girl, who at age 17 or so finds out she is actually genetically male but with Complete Androgen Insensitivity (hence 100% female-looking rather than the 90-something most women are).
Or worse, those women born with 5-alpha-reductase-deficien
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DUP!! (Score:5, Funny)
Re: DUP!! (Score:5, Funny)
They need a different term besides "Chimera" (Score:5, Funny)
No matter how many times I hear the biological equivalent of the term (which is never as exciting) I'm always let down. I always think some giant monster has been discovered, or someone turned into this monster, or geneticists have new clues as to the cause of this monster.
It's a bit annoying once I'm letdown but for a precious few seconds I'm always aghast in wonder.
Solidarity (Score:2)
One of these days, something from the Monster Manual is going to happen.
I don't know if that's good or not.
While it would be cool to see a Mind Flayer wandering about, it's probably not a good start to the day if you run into him.
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I see you've met my wife, then.
Serious question (Score:3, Insightful)
(I'm sure it is, it just seems.. moot to me).
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Re:Serious question (Score:5, Interesting)
talk about deja vu!
Some time ago, I wondered about the exact situation this article raises.
http://science.slashdot.org/comments.pl?sid=130374 &cid=10879347 [slashdot.org]
At the time, it fascinated me because it occured to me that you could have twins which share a maternal set of chromosomes but have one sex chromosome from the father be an X for one of the siblings and the other be a Y.
In other words, almost identical twin brother/sister pair! One wonders how much of gender is actually in our genes. Well, to have a pair of individuals share so much with the exception of the sex chromosomes - it becomes more reasonable to do an actual comparison. (I am aware there is still lots of room for genetic variation from the rest of the father's somatic set) I don't know how scientific it would be, but as a thought experiment, I wasn't to concerned about it at the time I posted it.
Re:Serious question (Score:5, Informative)
There's actually an interesting story, almost the flip side of this rare case in humans, running now in the New York Times about marmosets [nytimes.com], in which a form of chimerism is quite widespread:
"Corrective" Surgery. (Score:2)
Well, for the hermaphrodite twin, the implications are "corrective" gential surgury, followed by lifelong hormone therapy. Whether this is needed or even works at all is largely a secondary issue. You should read up about the expieriences of people born with ambiguous genitalia and the sufferring they have to endure at the hands of modern medicine and psychiatry.
No more jokes (Score:2, Funny)
This isn't new... (Score:5, Interesting)
There seems to be a hot debate over the possibility of this happening. Some scientists fully support the notion that this happens, while some have rejected the notion altogether, citing that polar body's don't "normally" contain enough cytoplasm to sustain themselves. But this sounds like a rediculous arguement, to me, since the exact amount of cytoplasm that is both required for fertilization, and the exact amount that a polar body usually contain, very wildly.
Unfortunately, it's very difficult to confirm whether or not this occurs, since percentage of difference in genetics between both fraternal twins and polar body twins is not exact. Polar Body twins will always contain between 50% to 100% of the same genentics (averaging at 75%0, where-as fraternal twins could be anywhere between 0% to 100% similarity. So, my friends will never actually know whether they developed from identical zygotes, but their genetic makeup was similar enough, that many doctors speculated that this was the case.
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I'm not so sure about "p
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While in theory siblings can share 0% genetic code (At least, 0% of the genetic code that actually differs among humans.), male siblings must share at least a little. There's only one possibly source for the Y chromosome.
Incidentally, this article is talking about polar body twins, but ones that 'merged' and then 'unmerged', or, more technically, separated incorrectly. Instead of splitting when first fertilized, they split later, along non-genetic lines.
This resulted in two people who had both sets of gen
Tommo and Hawk (Score:2)
I for one... (Score:2)
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Why this is notable: Cortical reaction (Score:5, Informative)
According to my anatomy textbook, after the spem digests its way through the zona pellucida:
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1) The article contains no language implying that the egg was fertilized by sperm from two different males. That was your own misinterpretation. The reason, by the way, that it would be impossible for two different fathers to fetilize the same egg in a human is due to the same factors making it unlikely for it to happen with one father--the egg only lets in one sperm at a time. The sperm would have to reach the egg at the same time. Only a porn star could receive sperm from two
Different donors? (Score:2)
Why? In various tests it can be shown that some people's "swimmers" are faster than others. So maybe person (a) had the lazy backstroke variety while person (b) had the olympic athlete variety. What's the optimal time to reach destination, and I've heard that it be in excess of an hour... which is plenty of time for things to happen with two donors.
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Marmoset family (Score:2)
Deliverance (Score:2)
023AD01('Semi-Identical', 'Twin') (Score:2)
Soul Arithmetic (Score:2)
This story poses an interesting challenge for those people blocking stem cell research on religious grounds.
The concept of the soul entering the zygote at the moment of conception raises puzzling questions when the resulting cell goes on to split into two viable individuals. What happens to the soul? Is it split in two? Does another soul enter the second? What happens when the individuals are not identical, do we get another soul?
The situation becomes even more unte
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I think the subject is miscatagorized (Score:2)
Basically each chimera has two sets of semi-identical DNA. The identical portions inherited from the mother make it possible for the DNA to be identical enough to interface and mix together to create a single entity. The TWO stains of DNA are 3/4 average identical. But for the DNA to be compatible enough that the child is viable is rare.
It's possible to have two children 3/4 identical just by chance. You would
chimera? (Score:2)
Or, it could be that the parents are named Typhon and Echidna.
In a slightly related note: we've seen on slashdot FA about mouse with human braintissue, recently sheep with 15% human DNA in it, etc. I'm curious how far one will go in this, and where to draw the line. I can accept most human-like organs grown in animals for the benefit of medical advancement (e.g.replacing ones' organs without the current difficultie
little clarification (Score:2)
I had to think about the SF-book 'startide rising' where dolphins and apes are genetically altered to be as intelligent as us. If we ever create a chimera individual (or a race) with an intelligence comming close to our own (note: how to evaluate that, though?) they should have the same rights as ordinary people.
The problem is, you will always have a grey area.
Then again, I already think expirements on
chimeras not all that rare (Score:2)
I remember seeing a case on Dateline TV where a child was removed from a mother because the standard DNA test did not match, even though the immediate footprint taken at birth did match. Turned out to be a rare case of father's mitochrondia. Same issue with the identificati
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However, I have heard of women having fraternal twins by two different men. So "semi-identical" twins by two different men would be an extremely rare and interesting bit of news, since the twins would each have genetic material from both
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Maybe some women should try for this to achieve notoriety and advance the cause of science...
Does Freddy Krueger count?
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Umm, no they wouldn't. They're semi-identical because they're from the same egg but different sperm. If there was a double-penetration act each semi-twin would still have a distinct father, but share since they shared the same egg, would share the same placenta and traits inherited from the mother.
To the casual observer, the two would appea
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According to this, in these chimaera-twins, each sperm contributes genes to each child. So if the sperm were from different fathers, the resulting twins would each really have tw
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I don't even want to imagine the scenario that would be required to get two sperm from two different fathers to fertilize one egg at the same time.
From what I remember from biology, almost all fertilization often happens when the egg drops into place, and the sperm is just hanging around already there. The 'sperm swims to the egg' is a fairly large over-simplification of the process.
This is how the morning after pill works, it stops the release of the egg so it won't hit the sperm waiting for it, or at
Re:wow, that must be embarassing (Score:5, Funny)
And the plot for the next gang-bang porno suddenly comes into view.
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