Do identical twins have the same DNA?

Question

I was talking to someone who said that her cousin could be considered to be her brother because both of their mothers are identical twins.

Answer 1

Identical twins have exactly the same DNA. They are the result of a single fertilized ovum (egg) that somehow during the process of multiplying and dividing split apart. It is thought to happen when a great number of cells on the left side of perhaps 200 cells divide at the same instance with so much force they literally knock cells loose on the opposite side. Kind of like what happens during the first shot of a game of pool. The two seperate clumps of cells now have identical DNA and must attach to the wall of the mother in order to survive. Oddly enough even though they have identical DNA they do not always like the same things. One may like the color red where the other likes blue. One will like fish the other beef. It is a testament to the human mind that they can be so identical in physical makeup and yet have seperate personalities.

As far as the cousin, the closest they could be is HALF brother/sister because they have seperate fathers. But that is an interesting situation, if say, the fathers also were identical twins.
HMM that could really change the meaning of immdiate family couldn't it?

Answer 2

Identical twins have the same DNA, however because the cousins have different fathers, they will have no alleles in common with the other one's father. So they would not have the same genetic link that two brothers would have (only half-brothers.)

If the identical twin mothers were married to a pair identical twin fathers, then the cousins would have the amount of alleles in common that brothers would have. They still could not be considered brothers though because they don't have the same parents, they have different parents with the same DNA.

Answer 3

Yes the identical twins have the same DNA, I have heard that before. Because if they are trying to find a father of a child, I saw on tv, they can't determine if the child is from which twin if they have both been with the woman. You never know whats true on tv though.

But they still have different fingerprints for some reason.

Answer 4

Identical twins have the same DNA.

Answer 5

Sounds good to me. Identical twins do share the same DNA.

Answer 6

From the moment some twins are born, parents are certain of one thing—they aren’t identical! Perhaps they have different hair or skin colors, or perhaps, like my twins, one has a distinctive hereditary mark (a cleft chin) and the other does not. But many parents of twins are uncertain if their twins are identical or fraternal. In these cases, performing a simple, painless DNA test can give parents and twins the answer.

DNA testing has revolutionized the world in many ways. These tests have made it possible to prove or disprove paternity in child support and/or custody battles; DNA testing has proven the innocence or guilt of suspects in criminal cases. DNA tests can also help find matches for those who need organs or other body tissue transplants.

Answer 7

Identical twins do NOT have identical DNA, because at least ONE thing is ALWAYS different in EVERYBODY, even identical twins. sure, they MAY have the same chromosomes, most likely NOT, but still, they'll be arranged differently.

also, the person's cousin could only be considered their HALF brother, not full-blood brother, because their fathers are different... unless..... NO! im not gonna even get INTO that!

Answer 8

identical twins come from the same egg, it splits when it's fertalized, therefore the twins have the same dna. but i wouldn't consider a cousin to be a brother. wow, i've never thought it that way.

Answer 9

Yes. Identical twins have identical DNA. That's why they're identical.

Answer 10

Identical twins have the same (identical) DNA, originally. They start out as a single zygote.

The original zygote splits, at an early point in it's development, into two embryos, both of whom have the same characteristics as the original zygote.