Home > Your genes > Where did your genes come from? > Epigenetics – beyond the human genome?

Epigenetics – beyond the human genome?

Nearly every cell in your body contains the same set of around 24,000 genes. The reason that your bone cells are different from your brain cells is that they use different genes. So how does each cell know which of its genes to switch on or off? Epigenetics appears to be the answer. Epigenetic mechanisms involve adding chemical tags to DNA or the proteins it is wrapped around. Changes to the cell’s environment cause the chemical tags to be added or removed. These epigenetic markers are passed on to daughter cells when the original cell divides in two.

DNA associates with histone proteins to form chromatin. Changes in the way chromatin is modeled can have epigenetic effects.