Can you change DNA methylation after birth?

How our parents shaped us even before we were born

A long time ago biologists argued about how animals get their characteristics. How did different species evolve over millions of years? For Charles Darwin it was later clear: it must have happened through heredity and many generations that his famous Darwin finches have certain beaks. His counterpart, the French Jean-Baptiste de Lamarck, on the other hand, advocated the thesis that individuals themselves can also change their shape through their will alone. If the fruits and leaves hang higher, the giraffe would grow a longer neck within a lifetime rather than many generations.

Lamarckism refuted - and yet explanations are missing

Today it is clear: Lamarck was wrong. And yet Darwin's findings do not answer everything that can be observed - for example with us humans. The pattern or the sudden accumulation of certain diseases, whether metabolic diseases such as diabetes or psychological problems such as trauma or depression, cannot be answered by inheritance alone. How can you explain that only one twin is susceptible to diabetes?

The mere sequence of our genome is not sufficient for these phenomena. This is exactly where epigenetics comes into play. Researchers want to use it to explain what has been observed so far but cannot be explained.

Epigenetics could provide answers to scientific puzzles

First of all, epigenetics is the way our genes are turned on and off. This process is also called gene regulation. If you think of our DNA as a kind of library, then epigenetics determines which books are accessible on the shelves and which are hidden in the archive.

And this is how it works: Our genes are sections on a DNA strand or on the DNA double helix. In order for genes to be read, they have to be exposed or have proteins attached to them that give the signal: read now. In the same way, however, the strand can be wrapped around protein balls and thus inactive. Or other biochemical molecules accumulate that decide whether our genes are activated or not.

More and more processes are becoming known that can have epigenetic effects. We show two of them in the following graphic:


If we stick to the idea of ​​a library, then information is stored there for dealing with all situations in life. Acetylation or methylation, i.e. the indication of which books are accessible and which are not, makes every human library unique. If you imagine a list of all books, some of which are archived, others directly accessible, the result is a sample. This can change in the course of our life. So epigenetics is constantly changing our properties and hereditary traits.

Researchers have observed various control mechanisms. Combining them would result in an almost infinite number of possibilities as to how compact and closed or how open and accessible DNA is. We would not understand such a complexity at the moment. It is also conceivable, however, that patterns have been established showing how individual regulatory processes interact with one another. But that will keep researchers busy for decades.

First of all, however, these observations mean that the individual can actually adjust to the environment during his or her life.

Epigenetics is a mystery, multi-generational and trans-generational epigenetics all the more

But there is another point that is particularly important and exciting for us here: Because some of the epigenetic information can also be inherited - and not only shape one's own children, but also other generations. But it can also be changed within a lifetime. In this way, organisms or our bodies can react to changes in the environment, even though nothing changes in our genetic makeup.

One percent of the child's genes are susceptible to change before birth. In view of the total of up to 25,000 genes in humans, this is still very little, but they can nonetheless be important. So what we do and eat today may be reflected in our children and grandchildren. That can be good or dangerous.