Transposons are just small pieces of DNA that randomly insert in the genetic code. And if they insert in the middle of the gene, they disrupt its function.

Traditional ways of distinguishing populations are irrelevant in terms of genetic code.

We are going from reading our genetic code to the ability to write it. That gives us the hypothetical ability to do things never contemplated before.

It turns out synthesizing DNA is very difficult. There are tens of thousands of machines around the world that make small pieces of DNA - 30 to 50 letters in length - and it's a degenerate process, so the longer you make the piece, the more errors there are.

We can do genetics. We can do experiments on fruit flies. We can do experiments on yeast. It's not so easy to do experiments on humans. So, in fact, it helps us, to interpret our own genetic code, to have the genetic code of the other species.

Mitochondrial DNA is in higher concentration, lasts longer, and can be extracted from bones.