Epigenetics - genes are not fate

Christiane Fux studied journalism and psychology in Hamburg. The experienced medical editor has been writing magazine articles, news and factual texts on all conceivable health topics since 2001. In addition to her work for, Christiane Fux is also active in prose. Her first crime novel was published in 2012, and she also writes, designs and publishes her own crime plays.

More posts by Christiane Fux All content is checked by medical journalists.

Genes shape our appearance, our disease risks and even our personality. Classical genetics has taught this for many years. Conversely, we can also influence our genes, as the still young research branch of epigenetics shows. The genetic makeup is far less fateful than long thought.

Which genes we carry in us is determined from the moment of conception, but not whether a certain gene is actually active. In this way, the cell ensures, on the one hand, that only genes are read that are necessary for their specific task. Different genes are active in a heart cell than in a liver cell.

Disease genes cut out

On the other hand, environmental influences also influence which genes are active in the cells. A healthy lifestyle can mute or turn positive genes on. Conversely, an unhealthy lifestyle can cause disease-causing genes to jump in. Such epigenetic mechanisms enable humans and animals to adapt more quickly to changing environmental conditions.

So-called epigenetic markers, tiny appendages that are distributed along the DNA strand, play a key role in this. These methyl groups act like switches that can turn genes on or off. If they attach themselves to the DNA, they prevent the gene from being read. Scientists call this mechanism methylation.

Another way to inactivate genes is to simply stow them away safely. So that the long DNA strand can be accommodated in the cell nucleus, it is wrapped around certain proteins - so-called histones.The genes can no longer be read in sections where the coil is very tight.

Lifestyle as therapy

In the meantime, epigenetic changes are already being tested as a therapeutic option. For example, it has been found that men with prostate cancer benefit from positive lifestyle changes. A few weeks of daily walks, a healthy diet, and relaxation exercises were enough to deactivate several hundred genes - including those that promote cancer.

Particularly great astonishment was caused by the fact that epigenetic imprints not only change the individual in question, but can even be passed on to the descendants.

This is shown on the one hand by impressive animal experiments. For example, a certain strain of mice, the agouti type, is usually obese, has light-colored fur and is at high risk of diabetes and cancer. However, if the females were fed a diet high in vitamin B12, folic acid and choline, their offspring were slim, dark-coated and very healthy.

Inherited Experience

Some epigenetic influences have already been demonstrated in humans, which are passed on to the offspring. For example, children of mothers who had to endure abuse during pregnancy are over-sensitive to stress and develop a more fearful disposition. This makes sense from an evolutionary point of view: the children are more cautious and better prepared for an unsafe, potentially dangerous environment.