of Mice ...

All living things on Earth have something in common. Four basic elements - A, T, C, and G - make up our genes. The diversity of our planet's living organisms comes from countless different combinations of these four basic elements.

	Mouse.

The similarity between humans and other living things is especially strong when we look in detail at the genetic makeup of organisms such as the mouse, with which we share a common mammalian ancestor. For these species, both the number of genes and the way in which they are combined are very similar to ours.

	Coloured X-ray of the skulls of a chimpanzee and a human.

Ever thought that a chimpanzee seemed almost human? The closer the relationship between different species, the greater the similarity between their genes. In fact, the genetic makeup of a human is over 98 per cent the same as that of a pygmy chimpanzee.

What about living things that do not appear to be at all alike? Almost ten per cent of human genes are related to certain genes in creatures like flies and worms. So, we even share some of our genetic makeup with unlikely relatives.

... and Men

On the surface, humans seem very different from each other. Indeed, we are all unique - but we are also very much the same! Genetically speaking, the most that any two people differ from each other is only 0.01 per cent.

The sequencing of the human genome has revealed the astonishing similarities that exist among all living beings, from humans to bacteria. We now know that every form of life is the product of the arrangement of A, T, C and G.