How do epigenetic markers influence behavioural changes over generations?

Epigenetic markers can influence behavioural changes over generations by altering gene expression without changing the DNA sequence.

Epigenetics is the study of changes in organisms caused by modification of gene expression rather than alteration of the genetic code itself. These changes can be passed down through generations, influencing behaviours in offspring. Epigenetic markers, such as DNA methylation and histone modification, can turn genes on or off, thereby affecting the production of proteins in certain cells. This can lead to significant changes in behaviour.

For instance, studies have shown that traumatic experiences can leave epigenetic markers on the DNA, which can then influence the behaviour of future generations. In one study, mice were conditioned to fear a specific smell. This fear was then passed down to their offspring, who also exhibited fear of the smell despite never having been exposed to it. This was due to epigenetic changes in the DNA of the parent mice, which were then inherited by their offspring.

Similarly, research on humans has shown that children and grandchildren of people who have experienced trauma, such as survivors of the Holocaust or the Dutch famine, have different stress hormone profiles to those without such a family history. These differences are thought to be due to epigenetic changes passed down through generations.

Moreover, epigenetic changes can also influence behaviours related to health and disease. For example, diet and lifestyle choices can leave epigenetic marks on our DNA that can influence the risk of developing diseases like cancer and diabetes. These changes can also be passed down to future generations, influencing their health behaviours and disease risk.

In conclusion, epigenetic markers can have a profound influence on behavioural changes over generations. They can alter gene expression, leading to changes in behaviour that can be passed down through generations. This is a rapidly growing field of research, with potential implications for understanding the heritability of behaviour, disease risk, and the effects of environmental factors on gene expression.