Identical twins DNA. Are identical twins DNA profiles also Identical?

Answer 1

Identical twins have identical DNA. Phenotypes expressed may be different such as fingerprint is a result of the folding on the skin. They are 2 different things. I have explained that in another of answer about fingerprint. I have some sources that states that identical twins have identical DNA.

Answer 2

Yes,

Identical twins start out with the same DNA, but there have been minor changes in mutation that differentiate them among the 3 billion or so letters of their DNA. That is not a big deal as we all have "mutations" and there is probably more than a couple of DNA differences between your left and right hand within the same person. For practial purposes this does not matter. When a lab makes a DNA profile, they are only looking at a relatively small subset of all 3 billion letters. Odds are that even though the twins may not be entirely identical, the subset of DNA that is "profiled" will almost certainly be.

Answer 3

You seem to have a mixture of yes and no answers there!

Here's the thing about DNA

Truth be told, for identical twins, the DNA sequence will not be identical for every single one of the 3 billion or so bases. It was initially thought that the DNA of monozygotic (same egg) twins would have identical DNA, however more recent studies have highlighted tiny differences that occur after the initial split during embryo and foetus development (referred to by one of the above answers i think).

Testing for these differences however is a different story and would be a time consuming and costly process.

For the purpose of DNA fingerprinting (forensics and such) the standard DNA profile obtained for two identical twins would almost certainly be indistinguishable from each other. A much more comprehensive test would be needed to tell them apart.

Answer 4

The answers so far are of mixed correctness. Since identical twins arise form the same fertilized egg, then the do indeed have the same genetic background, and for most purposes are considered to have the same DNA. Generally, if samples from both were tested, it would not be possible to tell if you were looking at the same sample twice, or one from each twin.

However: as has been pointed out, every round of DNA replication creates random errors. So, after just one cell division, both cells are already different and this will continue with every suceeding division. In that sense no two people are identical, not even identical twins. But it is worth remembering that for the same reason no two cells in your body probably contain exactly the same sequence either. So: identical twins are statistically as similar to each other as they are to themselves.

As usual, no simple answers

Answer 5

First you need to realise that there are 2 types of DNA, nuclear and extra nuclear. The nuclear DNA is the one that is inside the cells' nucleus, and in identical twins, this is identical (without counting mutations of any sort). The extra nuclear DNA is the one contained in mitochondria and plant's chloroplasts. This DNA is inherited directly from mother to offspring, and this DNA varies in twins, but it's very small. The phenotype, or appearance of twins is changed by the environment, just as it happens with anybody, so after all this, twins are not identical when you see them, strictly speaking, and their whole DNA is not so identical strictly speaking, but their nuclear DNA is definitely identical.

Answer 6

No... a full human DNA profile is identical to each person, and would be different in identical twins . In a persons lifetime, small mutations will occur in fragments of the DNA, so a full DNA profile would reveal differences.

The DNA profile they use in forensic analysis would appear identical however, because only a few sites are taken and therefore a small chance or any differences. A full DNA profile would be time consuming and expensive.

Answer 7

Identical twins have the exact same DNA sequences when the embryo initially splits in two (if the split is perfect). From the point when one embryo becomes two, the possibility of mutations can create differences between the two genetic sequences. Obviously the older the identical twins are, and the greater number of toxins, carcinogens, etc. that one of the individuals is exposed to leads to a greater number of genetic variations between the two.

Answer 8

Well yes and no... The DNA between identical twins is NOT the same, BUT and its a big but (not in the Sir mix a lot way) they are similar enough that the DNA of one twin could be the DNA of either...

Answer 9

no 2 DNAs are identical.

identical twins are still different
although it is possible for twins to be identical and therefore they would have identical DNA. But it has never happened

Answer 10

yes. identical twins = identical DNA