can two people have the same dna?
150252
Yes it can, and depending on the DNA sequencing technque and the ancestry of the peole involved it might be quite high.\n\nRemember criminal DNA sequencing doesn't test the whole genome. It only tests a tiny fragment, less than 0.01%. It is estimated that the chances of even such a tiny fragment matching the worng person are less than 1 in a million, but studies over the past few years have indicated that certain populations, such as some Jewish groups, may have much higher chances of random matches. \n\nEven at 1 in million that means thatin a major city like New York or Los Angeles there may be a dozen peole walking arund who match you perfectly.\n\nIn practice people don't get indicted or convicted on the basis of DNA alone. There has to be some other evidence linking them to the crime, even if only circumstancial. Aside from that the law in the US only requires level of proof beyond reasonable doubt. A doubt of less than one in a million is way below the reasonable level.
558247
Do they have the same fingerprints? "No," says Professor McCabe. Actually, it takes a while for these clumps of cells to get fingers, let alone fingerprints. So we're talking about on down the road a ways.\n         But still, how can this be? How can two people who have EXACTLY the same genes be different? After all, it's our genes that control everything about who we are and how we grow, right? So what's going on here?\n         Already when the embryos are in the womb, parts of their ENVIRONMENT are affecting what they'll be like, says Professor McCabe. Even though these babies are in Mom's womb at the same time and have exactly the same genes, many things can have different effects on each baby and can cause them to be different. For example, one baby may be getting a bigger part of Mom's blood supply and therefore more food than the other, so one identical twin may weigh more than the other at birth. Other effects include their position in the womb, Mom's mood, Mom's health, and so on.\n         Now, what about fingerprints? Can differences in blood supply give rise to different sets of fingerprints? Well, we don't really know, says Professor McCabe. (Sound familiar?) The difference could be due to many different environmental effects in the womb during the babies' development.\n         Other things about identical twins can be different. Professor McCabe showed me a picture of twin boys. Their hair whorls, the way the hair twists in a spiral pattern on the back of the head, turn in opposite directions! Here they are, absolutely alike (kind of), but their hair twists in opposite ways. What causes it? Who knows? \n        Whatever it is, it also makes other things different in these otherwise identical twins: the structure of their brains, for example, and how they think and learn.
394370
I'm pretty sure under the SA law, as well as any federal laws, a person does not have to disclose any confidential evidence without charge to authority, or other lawful reason. So unless your friend can get a warrant, I'm afraid both men's DNA cannot be tested without approval. \n\nFrom your question, your friend should have contact with the other. Perhaps she can convince that person to do the DNA test. Otherwise, she can resort to hiring private detectives and see what they can do.
12247
actually, that's not 100% true.  identical twins have the same genotype at birth, so most simple paternity tests would NOT be able to tell a difference.\n\nHowever, as twins age (and we hope they have if you're sleeping with them), certain genes are activated in one and not in the other.  This means that more sophisticated genetic testing MIGHT be able to tell a difference.\n\nOtherwise, we figure you're pretty safe.  I hope it was a good threesome!
496128
DNA can trace a long ways back. There are "markers" that persons of the same relation will carrying. one set of markers is for your mothers side and another from your fathers side. if i rememeber right the mothers side is a little eaiser to trace back. :)
769528
As the mother of identical twins I hear these types of questions alot:\n\n1. Identical twins are from the same fertilized egg which splits.  They have the exact same DNA which means their blood type is also the same.\n\n2. Fraternal twins are from two different fertilized eggs.  They are brothers/sisters who happen to be born at the same time.  Biologically, they are as similiar as any other brothers/sisters.  They could have the same blood type but they may not.  They will not have the same DNA.\n\nHope this helps!
1126486
They have to do this because only certain parts of DNA are used to ID people. And so much of DNA is similar they prove identity with statistics. So the likelihood of the DNA being the specific person is 1 in 20000 and that linked with other evidence is often more than enough to prove guilt or whatever. There is a law of probability and when things are put together it is very reliable.\n\nOk I am adding on in response to your question. I have consulted a textbook and think that the test described above is pretty conclusive. The textbook describes running a gel with the DNA fragments on it. They space out and are very obviously different to each other and are compared to the original. (see example of gel here http://gallery.hd.org/_c/natural-science/_more1999/_more05/DNA-genetic-fingerprinting-dark-bands-in-gel-are-almost-unique-for-a-given-individual-tweaked-1-AJHD.jpg.html) . Another thing mentioned in my textbook is taking samples from commnunities to compare blood samples. So one could suggest that they took samples of blood from 20000 people in the neighbourhood and only the one persons blood dna fingerprint matched up.
571791
It is medically possible at this point in time. A fertilised human egg (that has already made contact with sperm) is frozen while it is still a single cel and hasn't duplicated. Under a microscope scientists insert a needle and remove the cell nucleus that contains the DNA of the merged egg and sperm. They then insert a nucleus from the host person that contians their own DNA. The cell is then allowed to divide and continue growing, at the right time it would be placed within a surrogate mother like test tube babies until a baby is born with the exact DNA of the host person. Barring developments later in gestation such as the mother's diet and condition, the child will be an exact duplicate of the host who's DNA was used, until social factors kick in
925111
Something like 99.9% of any two humans genomes are identical.  Most of the differences between any two peoples genomes are single base differences in the junk DNA (most of your DNA which doesn't do anything). It is really a small number of differences between people that make us each genetically unique and different from all others. Those are just very small differences in a lot of the genes that we all have.
291295
DNA doesnt change as you grow or age, its stays the same throughout your life.
625549
looking for relatives via DNA
1131654
OK, *some* twins are genetic clones, in that they have identical DNA because they come from a single egg and a single sperm.  Most twins are not genetic clones and are in fact fraternal, coming from two different eggs and two different sperm.\n\nAs the parent of identical twins, I can tell you that they have a lot of differences.  They don't "share a soul" so that they can communicate in some romanticised twinspeak thing, although they do relate to each other extremely well and often feel similar emotions, but then they are usually doing the same activities and having the same experiences, so there is nothing mystical about that.  \n\nTHey are each an individual and they have their own individual likes and dislikes.  They like a lot of similar things, like their favouirte colour and games, but then that makes them similar to just about every other 3 year old girl on the planet too.\n\nBut lets get right to the point:  God caused them to come into being.  God gave them each their own soul.  They have the right to be recognised and valued as individuals.  Twins are very special and identical twins are rarer and so thought of as even more special - it is always a novelty for people to see people who look exactly alike.  But as a parent of two other children who are not twins, I can also say that every single person born is just as special.  Lets not bestow multiple birth children with mystical qualities.  Lets just let them be kids.  They get enough unsolicited attention and advice as it is.
619446
I assume you're talking identical twins.\n\nThey'll look as alike as the children of any normal couple. \n\nSince the mothers and fathers are genetically identical, it makes no difference (genetically speaking!) whether\n- one of the twin males marries one of the twin females\n- twin males both marry twin females\n- one of the male twins produces children with both female twins\n- one of the female twins produces children with both male twins.\n\nIn all of the above cases, all of the children will (genetically) have the same mother and the same father!\n\n\nGenetic relatedness can be expressed as a number, from\n1 = genetically identical (i.e. twins), to\n0 = not related at all.\n\nFor any particular gene (which we can think of as controlling one particular physical attribute), this is the probability that the two individuals have the same "version" or allele of that gene.\n\nThe higher the number, the more alike two people are LIKELY to be, although the way genes interact is complex and barely understood. So even though brothers and sisters have an average relatedness of 0.5, you may get some that look so similar they could almost be twins, while some look completely different to one another.\n\nFor two sets of identical twins marrying, average relatedness of their children is 0.5 (same as brother and sister)\n\nFor one set of identical twins marrying one set of non-identical twins, relatedness of their children is slightly less at 0.375\n\nFor one set of non-identical twins marrying another set of non-identical twins, relatedness of their children is 0.25 (same level of relatedness as half-brothers or half-sisters, and double the normal relatedness of first cousins which is 0.125)\n\nInteresting thought that if you and your brother or sister marry two children from another family (as happens from time to time), your respective children will effectively be half-brothers and half-sisters to one another!
1082706
With todays DNA testing the answer must be Yes !\n\nAnd when it comes back of course you can ... everyone needs a hobby.
152790
Both parent were heterozygous
251848
Well there are so many technicalities revolving around this question. While biologically speaking you could call the children sibblings is erelevant to the question. Manly because they will have there own genetic codes.  That is where this becomes quite complicated because genetics deals with more than just genes it deals with traits, DNA, Chromosomes, Blood Types, etc...  As far as them being related, coming from not only the same father, but an identical twin they are going to have very similar genes.  In fact when it comes to there family traits it will be identical.  However no individual, no matter if they are identical will ever have the exact same genetics (in the broad since) as another because that would go against the natural law of diversity.  So sumary exact same family traits, but overall two different people (genetics).
145244
It is called Chimira(sp) one twin is absorbed into another and usually it is the semen or egg that has the different DNA.  the Saliva and blood are the actual person's DNA and the other is like a brother or sisters DNA