Question

What forensic materials have DNA?

Answer 1

If you look at blood cells, the red blood cells have no nuclei. Only the white cells will have nuclei (DNA). These are the ones that you can use for comparisons.

As far as hair, only those with the root attached can be used. The hair shaft has no living cells and therefore no DNA. The shaft can give other information such as drugs and poisons and even an idea when they were used.

The hair root has the DNA you may be looking for. See the root ?

There may be skin scrapings from under the nails which may contain DNA. BUT these have to be from the living layer of dermal cells .

And any semen found will have sperm which have DNA. The semen itself is just a fluid carrying nutrients for the fast swimming sperm.