Memories can be passed down to later
generations through genetic switches that allow offspring to inherit the
experience of their ancestors, according to new research that may
explain how phobias can develop.
Scientists have long assumed that memories and learned experiences built
up during a lifetime must be passed on by teaching later generations or
through personal experience.
However, new research has shown that it is possible for some information
to be inherited biologically through chemical changes that occur in
DNA.
Researchers at the Emory
University School of Medicine, in Atlanta, found that mice can pass on
learned information about traumatic or stressful experiences – in this
case a fear of the smell of cherry blossom – to subsequent generations.
The results may help to explain why people suffer from seemingly
irrational phobias – it may be based on the inherited experiences of
their ancestors.
In the study, which is published in the journal of Nature Neuroscience, the researchers trained mice to fear the smell of cherry blossom using electric shocks before allowing them to breed.