Yes. [Added in response to thintaonga] Correct. However, it is nuclear DNA that is tested, that is identical and presumably is what was inferred by this question.

Identical twins have identical nuclear DNA (which is what most people hear about as DNA) but NOT exactly identical mitochondrial DNA. So the term "identical" twins is really not accurate, which is why scientists use the term monozygotic (which means arising from one egg). http://mypage.direct.ca/c/csamson/multiples.html

Yes as previously answered. But I have a feeling that the question might be asking if there is a difference if tested. They have the same genotype, but different phenotypes. So a test would show two different people.

Actually, although two of the answers seem to say that mitochondrial DNA differ in identical twins, this DNA will only differ through mutation in the individual. Mitochondria are acquired solely from the mother, via the egg, and in the absence of unique mutation will be identical to all cells split from the same egg -- and identical to those of the mother. So, under most circumstances, identical twins will have identical nuclear AND non-nuclear DNA. Thintaonga, mitochondria reproduce by cloning. Mitochondria are inherited solely from the mother, except for very, very, very rare exceptions; the mitochondria which enter with the sperm are normally destroyed. This means that all the mitochondria in a zygote are going to be identical to each other, and to the mitochondria of the mother, except where there have been errors in DNA replication -- i.e. the result of mutation, which is why we so often use mitochondrial "clocks" to date species divergence. It is certainly possible to have multiple mitochondrial "genotypes" in a single cell, since the mitochondria will replicate lines carrying a mutation which originated in a single source; however, there is rarely any huge difference, and for all intents and purposes, we are still talking "identical". If you have different information, please, please put up an answer with a cite to source. I would genuinely love to see it.

Not completly, but there are traits that are the same. I am a twin with my brother. We sort of look alike and do things together, but we do have our own personalities and differences.

Yes. Taken from Wikipedia: Identical twins occur when a single egg is fertilized to form one zygote (monozygotic) which then divides into two separate embryos. Although their traits and physical appearances are not exactly the same due to environmental conditions both in and outside the womb, they do have the same DNA.

According to http://www.wonderquest.com/twins-dna.htm, yes. Here's a question that someone asked on wonderquest.com: Q: April, some of my friends here have been arguing about a DNA test of identical twins. One says they should be identical;the other says they are different. -T.M.H.,Webster,N.Y. April Holladay, science correspondent, answered on Apr. 10, 2002: A: Your first friend wins. Identical twins have identical DNA. They come from the same fertilized egg, which had only one complete set of DNA in the first place. That fertilized egg and its single set of DNA split to form twin embryos-each with its own set of DNA, identical to the other. One small quibble: the DNA sets will be identical, unless one fertilized egg's DNA mutates. Such mutations, however, are normally so tiny that DNA analysis can't detect them. Suppose one identical twin commits a crime. How do you tell which twin did it if the DNA is identical? Well, you don't use DNA analysis since the DNA is the same. You dust for fingerprints. Genes only set the pattern for the fingerprint. The print develops in a placenta environment that differs somewhat for each twin. That, in turn, results in similar but different fingerprints. Photo: DNA patterns from four sets of twins-which are identical? Photo courtesy of Robert J. Huskey, U of Virginia

yes

Did you know Identical twins have different fingerprints?

Identical twins, formed when one fertilized egg splits, are the only people in the world with identical DNA. Fraternal twins, on the other hand, are formed when two different eggs are fertilized. Genetically speaking, fraternal twins are no closer than normal siblings, sharing only about 50% of their genes. Although identical twins have the same genotype, or DNA, they have different phenotypes, meaning that the same DNA is expressed in different ways. Traits determined by phenotype, such as fingerprints and physical appearance, are the result of "the interaction of the individual¿s genes and the developmental environment in the uterus." Thus, a DNA test can't determine the difference between identical twins, while a simple fingerprint can.

the DNA would be a very close match but not identical, just like the finger print which is not identical in twins...so there is always that slight difference even though we might not see it sometimes.

I believe so...seeing that on shows like Maury they can't tell who the baby daddy is with identical twins.

duh yes'

Don't you watch/read detective stories. Every amateur Hercule Parrot (sic with reference to Albert Moxey) knows they catch the wrong person first, and just before he goes to jail it's revealed he has a twin brother and it was the twin whodunnit

On CSI Las Vegas they did! Who needs school when TV is so educational.