The links between genetics and harmful substances in our environment
Our sensitivity to harmful substances is determined by our genes. But such substances can also reprogram our DNA, so called epigenetic changes, in response to the environment. Karin Broberg, Professor of Environmental Medicine specialising in Genetics and Epigenetics at the Institute of Environmental Medicine, researches these links between heredity and environment.
Karin Broberg researches on the links between genetics and harmful substances in our environment in terms of how these substances affect our DNA and how our DNA affects our sensitivity to the substances.
“The difference between people who are especially vulnerable to environmental factors and those who are especially tolerant is huge,” says Professor Broberg. “If we’re to be able to judge risks correctly and set suitable threshold limits for different substances, for instance, we have to know more about these differences.”
To a large extent, her research has focused on toxic metals and semi-metals such as arsenic, but her aim is to add to general knowledge in the field.
“Metals are a good model for understanding how toxic substances affect our DNA. For one thing, they’re relatively easy to track through the body. The metabolism of organic compounds is much more complicated.”
Genetic adaptation to hazardous environments
Professor Broberg and her colleagues have discovered what is to date the only known genetic adaptation in humans to hazardous environments: the indigenous peoples of northern Argentina exhibit genetic variants that enhance their tolerance to the high levels of arsenic in their drinking water. The findings were published in the spring of 2015 and widely disseminated and commented. The group has also shown that early exposure to harmful substances has an epigenetic effect that potentially impacts on health much later in life.
“Epigenetics is a relatively new and extremely exciting field. It helps us understand how environmental factors can have such a sudden impact on biology and why there can be such a delay between exposure and an increased risk of disease,” she says.
Text: Anders Nilsson, first published in "From Cell to Society" 2015. Translation: Neil Betteridge.