This epigenetics sketch was created by Armando Hasudungan, in collaboration with Professor Susan Clark and Dr Kate Patterson at the Garvan Institute of Medical Research. It has been created for a broad, non-expert audience to highlight key messages about the role epigenetics plays in biological processes like development and diseases such as cancer. To find out more: https://www.garvan.org.au/research/genomics-epigenetics

Our DNA contains our genetic code. There is almost 2m of DNA in each of our cells and each of our cells contains the same DNA sequence, the same genetic code. So how can cells that contain the same genetic code be so different? What makes a muscle cell different to a liver cell? The answers lie in tiny chemical tags that attach to the DNA, modifying gene structure and ultimately controlling gene activity. The chemical tags ensure that only some of the DNA code is used in each cell type, which means only some genes are switched on (expressed), while other genes are switched off. Epigenetics is the word used to describe the chemical information attached to the DNA. So while the DNA code in each cell is identical the epigenetic code is different, thus determining our cells’ unique identities.