In the last century, the question of how much nature vs nurture influences our development from embryo to adult has been debated furiously. Is our development driven solely by our genetic code, or is it influenced by environmental pressures? This is the question epigenetics seeks to answer.
Imagine the genetic code as a script, outlining which genes we should express. Epigenetics is the study of how this gene expression is regulated by environmental factors.
The environmental factors can range from the signals produced by neighbouring cells in a developing embryo to pollutants in the atmosphere. The importance of epigenetics can be demonstrated by the ways in which it influences health and disease. Scientists working in epigenetics have revealed that gene regulation via epigenetics can contribute towards mental health conditions, the likelihood of developing various cancers, drug addiction and respiratory diseases, to name just a few. Epigenetics allows for our genetic script to be interpreted in many different ways. This happens because of modifications that are placed on our genes.
These modifications coat the genes and act as epigenetic tags, labelling genes which need to be turned “on” or “off”. This means different genes can be expressed without affecting the genetic code.
It is not fully understood how or why epigenetic changes occur. Studies are starting to show that interactions with our environment are a contributing factor. For example, your food intake, the amount of exercise you do, if you smoke and what kind of toxins and chemicals you are exposed to can all result in epigenetic changes to our genetic material, and can thereby influence how our cells and ultimately our bodies behave.
Epigenetic variation is all around us. When a caterpillar changes into a butterfly, its genetic code remains the same but an entirely different set of genes are expressed. Male and female crocodiles are genetically identical, yet they look completely different. One way scientists have been trying to understand and monitor epigenetics, is by observing identical twins. Identical twins are conceived from a single egg, so they have the same genome. This makes them ideal candidates for genetic and epigenetic studies. By studying the epigenetic variation between twins, scientists are hoping to answer a question that has puzzled us for centuries. Since twins have identical DNA, why do we frequently find that only one twin in a pair develops a disorder such as cancer or schizophrenia, even when the two people have been raised in a really similar environment?
These studies have raised further questions, such as how heritable are epigenetic modifications? Are they reversible? Currently, researchers are working towards developing DNA demethylating agents such as Azacitidine as anti-cancer drugs, amongst other treatments in an attempt to reverse epigenetic modifications. The potential impact of this treatment is astonishing.
Large scale projects such as the Human Epigenome Project aim to “identify, catalogue and interpret genome-wide DNA methylation patterns of all human genes in all major tissues.” In doing this, scientists hope to uncover how genetics, the environment and disease are linked to further our understanding and diagnosis of human disease.
In celebration of this fascinating topic, we are holding a free public lecture “Epigenetics – Why You Don’t Have Teeth In Your Eyeballs” as part of the British Science Festival in Birmingham 2014. The session will be chaired by Professor Alice Roberts (University of Birmingham, UK) and will feature talks from Nessa Carey (Pfizer) and Bryan Turner (University of Birmingham, UK). After the talks, the audience will have the opportunity to ask questions and debate issues raised with our speakers.
Visit www.britishsciencefestival.org for more details of the programme.
When: Monday 8 September 2014, 15.30-17.00
Where: Lecture Theatre S02, Poynting Physics Building, University of Birmingham
Registration: Click here
The event is to celebrate 50 years of FEBS, is the British Biology Sections presidential address, and is jointly organized with the University of Birmingham.