So, what is Epigenetics?
Epigenetics refers to the study of heritable changes in our genome (the complete set of all our genes) that occur without altering the DNA or genetic code. Have a look and read below to learn lots more:
This series of sketch videos about epigenetics was created by Armando Hasudungan, in collaboration with Professor Susan Clark and Dr Kate Patterson at the Garvan Institute of Medical Research.
They have been created for a broad, non-expert audience. These videos use original illustrations that, together with simple, clear narration help to highlight key messages about the role epigenetics plays in biological processes like development and diseases such as cancer.
Tagging DNA: Mislabelling the Cancer Genome
How can cells that contain the same DNA be so different?
This simple question is posed right at the beginning of the latest 3D animation created by Dr Kate Patterson of the Garvan Institute as part of ‘VIZBIplus: Visualising the Future of Biomedicine’.
This wonderful Nature video compares reading DNA to reading sheet music:
Epigenome: The symphony in your cells
Almost every cell in your body has the same DNA sequence. So how is a heart cell different from a brain cell? Cells use their DNA code in different ways, depending on their jobs – just like orchestras can perform one piece of music in many different ways. A cell’s combined set of changes in gene expression is called its epigenome. Earlier this year Nature published a slew of new data on the epigenomic landscape in lots of different cells.
All living beings are made up of cells (humans have about 37 trillion cells!). In the nucleus of each cell, you’ll find our DNA. The sequence of DNA bases (A,C,T and G) defines our genes or genetic code.
Humans have over 20,000 genes on long strands of DNA, which is tightly packaged around structures called histones. Together, the histones and DNA are referred to as the chromatin.
In the nucleus the genetic code is ‘read’ and transcribed into messages (RNA), which is translated into proteins. These proteins then carry out the functions in each cell of the body.
Of course not all genes/proteins are required by all cells all the time – they are turned on (or expressed) and off somehow – this is where Epigenetics comes in!
‘Epi’ means on top of or above – so Epigenetics refers to mechanisms that affect genes from above, ie, not affecting the genetic code itself. We know of two main epigenetic mechanisms controlling gene expression:
1. DNA methylation, which chemically modifies the base C, altering how the genetic code is read;
2. Chromatin remodelling, which alters the availability of genes for reading.
Disrupted gene expression underlies many human diseases such as cancer; the study of both genetics and epigenetics will help us to further understand such diseases and help us develop preventative measures as well as novel medical treatments.
Want to know more?
Maybe some of your questions will be answered here:
What's the difference between Genetics and Epigenetics?
While Genetics is the study of genes, and variation in inherited characteristics due to differences in DNA sequence, Epigenetics is the study of heritable changes in gene expression that are not caused by changes in the DNA sequence – biological mechanisms that cause a change in phenotype (observed characteristics) without a change in genotype (genetic sequence).
Why is Epigenetics important?
Epigenetic gene regulation is fundamental to the life of all eukaryotic organisms; it creates phenotypic variation not only within an individual, but also between individuals. Epigenetic modifications allow cells with precisely the same genomes to adopt a multitude of phenotypes based on the activation of some gene regions and the silencing of others. In addition, epigenetic modifications that mediate genome function are responsive to and may be modified by environmental cues.
How can I become an Epigeneticist?
Most epigeneticists have undertaken molecular biology/biology courses in a science degree with honours. They then spend a number of years in post-graduate studies, usually to earn a PhD, followed by post-doctoral research. Many epigenetics labs, including labs associated with the Australian Epigenetics Alliance, take on interested undergraduate summer school students and honours students, through their affiliated universities, and may also accept interested work experience students.