Dark Matter: Dark DNA is a biological matter.
Dark Matter, the mysterious stuff that evidently makes up 27 per cent of the universe but can't be detected by conventional means. Dark DNA is the biological related of dark matter, in The sense that can't see it but it's still here.
Hiding with it might be some of the evolution deepest secrets. For example, in the sand rat, a species of gerbil that lives in deserts that are particularly susceptible to type 2 diabetes, a gene called Pdx1 that controls the secretion of insulin, is missing, along with 87 other genes surrounding it.
Some of these missing genes, including Pdx1, are essential and without them, an animal cannot survive. But the biochemical analysis of tissues shows the chemical products that the instructions from the missing genes would create.