For example, they may contain DNA that is toxic to the bacteria used to amplify them.

A cell, which contains DNA, is then taken from the animal being cloned.

Would the hair contain DNA that could be read in the year 3000?

All living things contain DNA, including some strands, called introns, which have no known function.

This segment contained enough DNA to account for several genes.

But of course in those cases they already knew that a sample contained DNA; the question was pinning down its origin.

A drop of blood or the root of a hair contains enough DNA for testing.

It is added to solution containing DNA meant for transfection.

Cells, containing DNA and the machinery for reproduction, didn't just happen!