Epigenetics: Living with a permeable genome
Associate Professor Maurizio Meloni is at the forefront of research into the emerging field of epigenetics, or how the environment can affect your genetic health and functioning.
A/Prof Meloni is a social theorist and scholar in the social study of science, in particular biology, genetics and epigenetics. His work taps into a growing movement in research that is bridging the disciplinary divides between scientists and humanities and social science researchers.
In particular, he is concerned with the implications of how scientific concepts like epigenetics are being used in debates, by governments and policy-makers, and what this means for the people and communities affected.
But just what is epigenetics?
It’s a form of genomic plasticity, or the capacity for the genome to react and adjust to environmental cues such as nutrition, stress or toxins through changes not in DNA sequence but in genomic regulation.
“Epigenetics can be defined as the study of all environmental factors that activate or inactive gene expression,” says A/Prof Meloni. “What is happening right now in epigenetics is that we are understanding that there is a wider impact of individual and social behaviours, be that smoking, pollution, food, stress, social inequalities or even trauma, on genomic functioning.”
“This is not just that the world around you can affect your health in a variety of ways, but that it can affect you and change you right down to the genetic level.”
“The most visible areas of investigation in the field of epigenetics with direct social implications are nutritional epigenetics, the impact of food on genomic regulation, and environmental epigenetics, the effects of wider environmental and social exposures such as toxins, stress or socio-economic status on the genome. A more speculative but very interesting area is transgenerational epigenetics which studies the long-term impacts of famine, and stress and psychological trauma, for instance the effects of traumatic events such as the Holocaust, war, or even slavery on genomic expression.”
“But this has ongoing implications as well, as epigenetics includes the notion that biological heredity is not just the transmission of DNA sequences, but that there is biological material that is passed on from one generation to the next beyond these DNA sequences.”
What this means is that the environment of one generation, and the effect it had on that generation’s genomic functioning, can be passed on to the next generation. These claims remain controversial today, but they are often cited to argue that famine or psychological trauma could end up directly affecting the children, grandchildren, or even descendants further down their genetic line.
… famine or psychological trauma could end up directly affecting the children, grandchildren, or even descendants further down their genetic line.
Epigenetics is being increasingly used in a number of debates on racial inequalities in health in countries like the United States, South Africa, Indian and even Australia, with a particular focus on Indigenous health.
“It’s attractive for policy makers, epidemiologists, scientists and people in general who are looking for explanations.”
“However, one of the key messages of my work is that these concepts are always double-sided and their uses have both costs and benefits. In one sense, it may be quite a dangerous idea that vulnerable populations who have been exposed to century-long exploitation, famine or poverty are not only socially-disadvantaged but also biologically disadvantaged. On the other hand, this can also be an attractive rhetoric for vulnerable groups to make claims about social justice or reparations on the basis that historical trauma is based on biological evidence.”
An important effect of recent epigenetic studies is highlighting just how important it is that we live in a good, healthy environment, and particularly what role governments and institutions have in ensuring those health environments.
“It’s an invitation to rethink health in a wider way which is not only about personal responsibility to optimise or avoid damaging your own genome, but it’s about social and institutional responsibility to make a better environment for everyone.”
Associate Professor Maurizio Meloni is a Chief Investigator on two Australian Research Council-funded projects investigating the impacts of epigenetics on minority groups around the world. The first, Impressionable Bodies: Epigenetic models of plasticity in the Global South, aims to investigate how epigenetics is reshaping notions of the body, heredity and biological plasticity in the global South using case studies in Australia, India and South Africa.
The second, Epigenetics and Indigenous Australia, with ADI’s Professor Emma Kowal and University of Adelaide’s Professor Megan Warin, will investigate how epigenetics is being received specifically by Indigenous Australians, and aims to identify the potential risks and opportunities that narratives of biosocial damage entail.