What's the best source of human DNA?
What is the best sample of DNA that I can make? Spit in a bottle, a scraping from inside my cheeks, a patch of dead skin off my elbow, a snip of hair or what?
Kat Arney got stuck in to this question.
Kat - To be honest, when scientists are doing things like genetic studies, the best source of DNA is actually the blood. Red blood cells don't have DNA in because they lose it as they mature, but white blood cells are packed full of it. So, a good sample of blood, you spin it down, you take out the white blood cells, nice and pure, get a good sample of DNA. But actually, Paul is a man and he has a great source of DNA in his trousers. Without getting too graphic about it, sperm is actually really fantastic source of lots of DNA.