Why can't identical twins be distinguished from each other using DNA fingerprinting?
913841
Because DNA is identical, and it is the unique genetic code from which we each emerge. With twins - DNA is the same, as are the chromosomes, but the proteins, cells and organs which are transcribed/expressed from that DNA may vary slightly.
754868
Hi! I'm the mother of identical twins.  Here's some facts:\n\n1. Identical twins occur when one fertilized egg splits.  It's a random act of nature and is not impacted by family history, age, ethnicity or fertility drugs.  Every pregnancy has a 1 in 250 chance of being identical twins.  Identical twins have the exact same DNA.\n\n2. Fraternal twins occur when the female produces two eggs and both are fertilized.  It can be influenced by family history or fertility drugs.  Advanced age or certain ethnicities also increase your chance of fraternal twins.  Fraternal twins are essentially brothers/sisters who happen to be born at the same time.  \n\nHope this helps.
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. :)
352493
Twins are of two types 1) Fraternal 2) Zygotic.\n \n1) The fraternal twins develop from two different eggs that are fertilized at one and the same time.\n In this case DNA strands may not be identical. Mostly they are not.\n\n2) Zygotic, Identical or Siamese twins develop from only one fertilized egg. It splits early in to two and both the halves develop in to full-fledged individuals. Only in such cases the DNA is IDENTICAL.The sex is also the same.\n  Where as in fraternal twins the sex also be different , one boy and the other girl. It is like two siblings born together.
771694
Each person has their very own specific fingerprints- noones is the same at all.  This helps to identify ALOT of criminals and when they find one at a murder scene say- they can lift the print and run it through their data base and find the moron who killed an innocent person!  Noones is the same at all- people have tried to burn their prints off or cut the tips of their finger tips to make them different but now alot of DNA testing is better when u find a palm print as well as the finger print.  We all kind of write with our hand resting on the paper so it can also be used to find a criminal!
363834
John is actually incorrect... our characteristics are not governed solely on out genes, there are many factors that are involved.\n\nSome characteristics such as hair colour and eye colour are govered by our genes, but we can actually appear differently depending on how we developed in the foetal stage of development, as well as injuries we may sustain, what we eat, how we live, and psycological responses that lead to hormonal responses (or vice versa). All of these can change markedly our characteristics.\n\nSome simple examples include 'wide feet', spinal malformation (eg. muscular scoliosis), asthma, and many more. Note that these may be influenced by genetics, but having the gene does not mean you get the characteristic.\n\nConsider that two identical twins can actually be told apart becasue one is often slightly taller, or slightly fatter or has different characteristics, however their genes are the same.\n\nConsidering that the environment in the womb during pregnancy can change a human's characteristics quite markedly as it can also change hormonal development, then we must realise that if you were to be cloned then your clone may look very different from you... although you will most likely look similar enough to look like siblings.
815639
DNA is in chromosomes. Chromosomes are in 23 pairs: 2 *different* copies of Chromosome 1, 2 different copies of C2, etc, in each person.  Whether you get your father's Chromosome 1 that he got from his mother, or the one he got from his father, is random with respect to which Chromosome 2 you get from your father. Same goes for your siblings. The chances of two nontwin siblings getting the same exact set of 23 5chromosomes from one parent are vanishingly small. The chances of siblings getting the same exact set of 23 chromosomes from EACH parent are .. well, it's essentially impossible. \n\nSame goes for the possibility that they would receive NO chromosomes in common - although it is theoretically possible to have siblings that share no genetic relation at all.\n\nDNA evidence is never 100% conclusive, but the tests that are widely used (if done properly) have such a small possibility of being wrong that they might as well be 100% conclusive. That's because there's just so much genetic material in any one person, it averages out ... makes it so that siblings are actually very close to 50% alike - even though they could be anywhere from 0 to 0% alike, in theory.
674863
I support the research on human cloning. The clones would be individuals just like the rest of us--there is more to what makes a person who they are than their genes. Look at identical twins--they share the exact same genome yet they are not exact copies of one another in experience, personality, skills, etc. \nI think the pertinant question is this: What are the ethical rules to follow when it comes to human cloning?
7536
Identical twins develop when a single fertilized egg splits in two, leading to two embryos. Because they both came from the combination of the same egg and sperm, they have identical DNA, barring the generally undetectable micromutations that begin as soon as cells start dividing. To a standard DNA analysis, they would be indistinguishable. Yet the parents of twins can usually tell them apart by subtle visual cues, and, while their fingerprints are generally similar, they are not identical.
651589
No! This is impossible!  DNA isn't compatible.
261054
That would be a violation of HIPPA, which provides protection for our medical records. I do believe that law enforcement officials can search for DNA matches of those who have given samples, but civilians cannot and, I believe, should not be able to. Your DNA is similar to those you are related to: your mother, father, siblings. Humans also share basic DNA sequences.
397057
I just want to point out the fact that xaviar's and gradwrkout's answers are both very good.  Identical twins are spawned from a single set of DNA, so in theory, they are completely identical.  Some cells will vary due to mutations during DNA replication and other DNA mutating events, but mostly they will be identical.\n\nHowever, epigenetics can change throughout a person's lifetime, without altering the actual base-pairs of DNA.  Epigenetic changes include DNA CpG methylation, which can silence certain genes, and is common in certain cancers.  Another example of an epigenetic change has to do with chromatin.  Chromatin is what DNA is called when it is bound to histone core proteins.  When people talk about chromosomes, the chromosomes are always bound to histone.  The histone cores have little protein tails that can be altered in certain ways, which affects when a gene can be transcribed/translated.  Epigenetic changes can occur based on how you live your life-- if one twin lives in california and the other in london, the differences in their lifestyles will reflect in epigenetic changes.  Everything from diet and exercise to sleeping, etc, affects epigenetics.\n\nSo to answer the question, yes, their DNA is essentially identical, but over the course of their lifetimes, epigenetic changes can make them significantly different.  Also, just fyi, epigenetic changes are heritable.
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
457615
yes - if the DNA sources were from the same individual - person.
978984
I'm the mother of identical twins and have been asked this question before.  Here are some facts:\n\n1. Identical twins are from the same fertilized egg which splits.  Identical twins have the EXACT SAME DNA.\n\n2. If a set of identical twin girls had kids with a set of identical twin boys then the kids would GENETICALLY/biologically be brothers/sisters.  (Emotionally/legally they would be first cousins)\n\n3. The kids would look as similiar/different as any other brothers and sisters do.  It would be unlikely for them to look exactly the same just as it is unlikely for brothers to look exactly the same.\n\nThere's a pretty good article about twins marrying twins at: http://www.twinstuff.com/twinswithtwins.htm\n\nHope this helps!
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!
732387
No you could  not have 4 identical twins.  Twins are two babies born at once.  at conception the egg splits and makes twins they share the exact same DNA there for can not go to prison based on DNA evidence.  On the other hand it is very very rare that you would get quadruplets that are identical but it is possible.  If they are all the same sex it may be the case.  I have a relative who has 2 sets of twins 10 months apart and they all look identical however they are not as it is impossible.  Hope this helps.  I come from a family with 17 sets of twins.  They say that it skips a generation however that is not always the case.