Small RNAs may hold key to hereditary trauma

A new study has revealed that short RNA molecules could hold key to understand the physiological processes underlying hereditary trauma.

The study found that traumatic stress alters the amount of several microRNAs in the blood, brain and sperm, while some microRNAs were produced in excess, others were lower than in the corresponding tissues or cells of control animals, which resulted in misregulation of cellular processes normally controlled by these microRNAs.

The findings showed that after traumatic experiences, the mice behaved markedly differently, they partly lost their natural aversion to open spaces and bright light and had depressive-like behaviours. These behavioural symptoms were also transferred to the next generation via sperm, even though the offspring were not exposed to any traumatic stress themselves.

Isabelle Mansuy, from ETH Zurich, said that they were able to demonstrate for the first time that traumatic experiences affect metabolism in the long-term and that these changes are hereditary.

Mansuy and her team are currently studying the role of short RNAs in trauma inheritance in humans.