Aa
would any of you know??
If a woman slept with identical twins and got pregnant, would a DNA test show who the father was?
COMMUNITY LEADER
Had you slept with anyone else, about a week or so after the end of your period? It might be someone in the middle, if the choice with the twins is either the day after your period ended (which is a little early though sperm can last a while in your system) versus two weeks after your period ended, which is a little too late for ovulation. Can you give any information about when your first ultrasound was, how many weeks along you were at that time, and when they said your due date was based on the ultrasound, and how that relates to both twins? If the only two guys you slept with were the twins, I'd guess it was the guy the day after your period versus the one two weeks after the end of your period. If I'm understanding you correctly.
Regarding whether identical twins have identical DNA -- first, are you certain they are identical? They might be fraternal, in other words, fraternal twins who happen to look a lot alike. (In which case, they have different DNA.) Have they ever had DNA tests to check this? and second, as beckyy28 says, there can be some subtle differences in the DNA of identicals,(see article following) but unfortunately it is not known (or was not at the time of the article) whether those happen as a result of life, or whether it is their inherent DNA from the start. If the subtle differences were there from the start, it is possible (but you'd have to talk to a specialist to find this out) that the difference might be seen in their child's DNA test.
From a legal point of view, if you can show that either guy's DNA is the DNA of the father, my guess is that the courts might hit both guys for a split of the child support, since neither can prove it is not him. (This has happened in tort law before, such as when in a hunting accident two guys shot into the bushes and hit a third guy. Both the shooters had to pay the damages, since it was impossible to tell which guy was the one whose bullet actually did the damage.)
Before you go that esoteric legal route, if you want, write back and tell me the dates and the info from your early ultrasound, and we can at least see if either guy is really in the right time frame to be the dad. You'll need that anyway if you intend to get a court order for the DNA tests. And, also mention, was there anyone else it could have been besides the twins? Fun as it is to talk about and focus on the studly twins and the dilemma, possibly if you slept with a third guy, he could be the dad and then all of the concern about having to talk to DNA specialists and lawyers won't be necessary.
The article:
The Claim: Identical Twins Have Identical DNA
By ANAHAD O’CONNOR
Published: March 11, 2008
THE FACTS
Phenotypically Concordant and Discordant Monozygotic Twins Display Different DNA Copy-Number-Variation Profile (American Journal of Human Genetics)
It is a basic tenet of human biology, taught in grade schools everywhere: Identical twins come from the same fertilized egg and, thus, share identical genetic profiles.
But according to new research, though identical twins share very similar genes, identical they are not. The discovery opens a new understanding of why two people who hail from the same embryo can differ in phenotype, as biologists refer to a person’s physical manifestation.
The new findings appear in the March issue of The American Journal of Human Genetics, in a study conducted by scientists at the University of Alabama at Birmingham and universities in Sweden and the Netherlands. The scientists examined the genes of 10 pairs of monozygotic, or identical, twins, including 9 pairs in which one twin showed signs of dementia or Parkinson’s disease and the other did not.
It has long been known that identical twins develop differences that result from environment. And in recent years, it has also been shown that some of their differences can spring from unique changes in what are known as epigenetic factors, the chemical markers that attach to genes and affect how they are expressed — in some cases by slowing or shutting the genes off, and in others by increasing their output.
These epigenetic changes — which accumulate over a lifetime and can arise from things like diet and tobacco smoke — have been implicated in the development of cancer and behavioral traits like fearfulness and confidence, among other things. Epigenetic markers vary widely from one person to another, but identical twins were still considered genetically identical because epigenetics influence only the expression of a gene and not the underlying sequence of the gene itself.
“When we started this study, people were expecting that only epigenetics would differ greatly between twins,” said Jan Dumanski, a professor of genetics at the University of Alabama at Birmingham and an author of the study. “But what we found are changes on the genetic level, the DNA sequence itself.”
The specific changes that Dr. Dumanski and his colleagues identified are known as copy number variations, in which a gene exists in multiple copies, or a set of coding letters in DNA is missing. Not known, however, is whether these changes in identical twins occur at the embryonic level, as the twins age or both.
“Copy number variations were discovered only a few years ago, but they are immensely important,” said Dr. Carl Bruder, another author of the study at the university. Certain copy variations have been shown in humans to confer protection against diseases like AIDS, while others are believed to contribute to autism, lupus and other conditions. By studying pairs of identical twins in which one sibling has a disease and the other does not, scientists should be able to identify more easily the genes involved in disease.
John Witte, a professor of genetic epidemiology at the University of California, San Francisco, said the findings were part of a growing focus on genetic changes after the parents’ template had been laid. This and other research, Dr. Witte said, shows “you’ve got a little bit more genetic variation than previously thought.”
In the meantime, a lot of biology textbooks may need updating.
Dr. Dumanski pointed out, for example, that as his study was going to press, the following statement could be found on the Web site of the National Human Genome Research Institute, the group that financed the government project to decode the human genome: “Most of any one person’s DNA, some 99.9 percent, is exactly the same as any other person’s DNA. (Identical twins are the exception, with 100 percent similarity).”
That, we now know, no longer appears to be the case.
THE BOTTOM LINE
Identical twins apparently do not have identical DNA.
***@****
Regarding whether identical twins have identical DNA -- first, are you certain they are identical? They might be fraternal, in other words, fraternal twins who happen to look a lot alike. (In which case, they have different DNA.) Have they ever had DNA tests to check this? and second, as beckyy28 says, there can be some subtle differences in the DNA of identicals,(see article following) but unfortunately it is not known (or was not at the time of the article) whether those happen as a result of life, or whether it is their inherent DNA from the start. If the subtle differences were there from the start, it is possible (but you'd have to talk to a specialist to find this out) that the difference might be seen in their child's DNA test.
From a legal point of view, if you can show that either guy's DNA is the DNA of the father, my guess is that the courts might hit both guys for a split of the child support, since neither can prove it is not him. (This has happened in tort law before, such as when in a hunting accident two guys shot into the bushes and hit a third guy. Both the shooters had to pay the damages, since it was impossible to tell which guy was the one whose bullet actually did the damage.)
Before you go that esoteric legal route, if you want, write back and tell me the dates and the info from your early ultrasound, and we can at least see if either guy is really in the right time frame to be the dad. You'll need that anyway if you intend to get a court order for the DNA tests. And, also mention, was there anyone else it could have been besides the twins? Fun as it is to talk about and focus on the studly twins and the dilemma, possibly if you slept with a third guy, he could be the dad and then all of the concern about having to talk to DNA specialists and lawyers won't be necessary.
The article:
The Claim: Identical Twins Have Identical DNA
By ANAHAD O’CONNOR
Published: March 11, 2008
THE FACTS
Phenotypically Concordant and Discordant Monozygotic Twins Display Different DNA Copy-Number-Variation Profile (American Journal of Human Genetics)
It is a basic tenet of human biology, taught in grade schools everywhere: Identical twins come from the same fertilized egg and, thus, share identical genetic profiles.
But according to new research, though identical twins share very similar genes, identical they are not. The discovery opens a new understanding of why two people who hail from the same embryo can differ in phenotype, as biologists refer to a person’s physical manifestation.
The new findings appear in the March issue of The American Journal of Human Genetics, in a study conducted by scientists at the University of Alabama at Birmingham and universities in Sweden and the Netherlands. The scientists examined the genes of 10 pairs of monozygotic, or identical, twins, including 9 pairs in which one twin showed signs of dementia or Parkinson’s disease and the other did not.
It has long been known that identical twins develop differences that result from environment. And in recent years, it has also been shown that some of their differences can spring from unique changes in what are known as epigenetic factors, the chemical markers that attach to genes and affect how they are expressed — in some cases by slowing or shutting the genes off, and in others by increasing their output.
These epigenetic changes — which accumulate over a lifetime and can arise from things like diet and tobacco smoke — have been implicated in the development of cancer and behavioral traits like fearfulness and confidence, among other things. Epigenetic markers vary widely from one person to another, but identical twins were still considered genetically identical because epigenetics influence only the expression of a gene and not the underlying sequence of the gene itself.
“When we started this study, people were expecting that only epigenetics would differ greatly between twins,” said Jan Dumanski, a professor of genetics at the University of Alabama at Birmingham and an author of the study. “But what we found are changes on the genetic level, the DNA sequence itself.”
The specific changes that Dr. Dumanski and his colleagues identified are known as copy number variations, in which a gene exists in multiple copies, or a set of coding letters in DNA is missing. Not known, however, is whether these changes in identical twins occur at the embryonic level, as the twins age or both.
“Copy number variations were discovered only a few years ago, but they are immensely important,” said Dr. Carl Bruder, another author of the study at the university. Certain copy variations have been shown in humans to confer protection against diseases like AIDS, while others are believed to contribute to autism, lupus and other conditions. By studying pairs of identical twins in which one sibling has a disease and the other does not, scientists should be able to identify more easily the genes involved in disease.
John Witte, a professor of genetic epidemiology at the University of California, San Francisco, said the findings were part of a growing focus on genetic changes after the parents’ template had been laid. This and other research, Dr. Witte said, shows “you’ve got a little bit more genetic variation than previously thought.”
In the meantime, a lot of biology textbooks may need updating.
Dr. Dumanski pointed out, for example, that as his study was going to press, the following statement could be found on the Web site of the National Human Genome Research Institute, the group that financed the government project to decode the human genome: “Most of any one person’s DNA, some 99.9 percent, is exactly the same as any other person’s DNA. (Identical twins are the exception, with 100 percent similarity).”
That, we now know, no longer appears to be the case.
THE BOTTOM LINE
Identical twins apparently do not have identical DNA.
***@****
And the second one is who i deal with. but once his girlfriend found out about me then he started saying the baby wasn't his.
That's where I really messed up at because no I didn't use protection with ether one. but I don't believe that the first one will take the DNA test because that's the one that has a baby on the way by his girlfriend. an she is like a month behind me..
Yes they can determine which is the father!! Google it. My husband is an identical twin and I've learned so much about twins over the years its ridiculous. Just because they are identical does not mean every single piece of dna in their bodies is exactly alike...
If the twins are truely identical there is absolutely no way to tell. There is no testing beyond DNA. You would have to go by likely dates
I would say by your story, it's more than likely the second brother you slept with because it was two weeks after your period, which is when most women ovulate. It would be hard cause they are identical and share the same DNA. Not sure how they would go about making sure which one the real father is but I'm pretty sure it wouldn't be the one you slept with a day after your period ended.
Wow sorry but that's kinda awesome! I'm not sure about the DNA but when I was reading this I was like "nothing sexier then a set of hot twins!" Good kick mamma!
To be honest it's real life. Around the time I got pregnant I was deep in my party life. I had my period then the day after I got off we parted an i went home with one. Like 2 weekends after we went to another party an i got too drunk an was mad at the one i did it with an ended up sleeping with the other one. thenn i popped up pregnant.. But the one i believe is my child's father said somebody told him something so he thinks its some other dudes an not his brothers. Plus the brother has a baby on the way as well ..
I have triplet little brothers. Two identical. N i tell them all the time,(the identical ones) Do not sleep with the same girl. Bc if honey gets pregnant ya gotta both be dads to one kid. They laugh but medically I'm right. I'm pretty sure that dna will turn up they are both the father........unless (plot twist) neither are.
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