Why do identical twins have the same DNA, but paternal twins don't?

Question

Why do identical twins have the same DNA, but paternal twins don't?

Answer 1

paternal twins arise from separate fertilizes eggs that were fertilized at the same time. thus different DNA.   Identical twins come from division of one fertilized egg into clones...thus identical DNA

Answer 2

identical twins are the same as paternal twins hun ;)

Monozygotic twins (identical) come from the same egg while dizygotic (fraternal) come from two eggs. Monozygotic twins share 100% of their DNA while dizygotic twins only share 50% of their DNA.  Monozygotics are basically clones while dizygotic are pretty much brother and sister, the reason for that?  Like I said before, monozygotic twin's come from the same egg and dizygotic twins don't.

Answer 3

FRAternal twins don't come from the same egg and sperm

Answer 4

Identical twins come from the same egg and single sperm cell that has split to form 2 individual people.   Fraternal twins are from 2 different eggs and sperm cells that happened to be fertilized at the same time.  The only difference between fraternal twins and other siblings is they were both conceived, carried and born at the same time.

Answer 5

Problem here - paternal twins are the same as identical twins.

Did you mean fraternal?

There are two kinds of twins. Fraternal twins are not identical. A set of fraternal twins occurs when two embryos implant at the same time. This means they can be the same s*x or opposite s*x. They might look similar, but they will not be identical. In very rate cases, fraternal twins can have different fathers or even appear to be different races if their parents are of two different races. Identical twins are called paternal twins. These twins are born from a single egg that split very early in pregnancy.

When a single, fertilized egg divides and separates, she has identical or paternal twins.

Answer 6

Identical twins were from the same fertilized egg, but it split into two.

Paternal twins are two separate eggs that have been fertilized at the same time. The identical egg contains all the same DNA, whereas the paternal twins have different combos of DNA due to segregation, crossing over, and DNA variety.

Answer 7

identical twins are from the one egg. The single egg splits into two after fertilisation, creating two genetically identical people. In fraternal twins two seperate eggs are released and fertilised.  

Answer 8

Identical twins came from the same zygote. Fraternal twins came from two separate zygote.