Using olfactory molecular specificity, we examined the inheritance of parental traumatic exposure, a phenomenon that has been frequently observed, but not understood. We subjected F0 mice to odor fear conditioning before conception and found that subsequently conceived F1 and F2 generations had an increased behavioral sensitivity to the F0-conditioned odor, but not to other odors. When an odor (acetophenone) that activates a known odorant receptor (Olfr151) was used to condition F0 mice, the behavioral sensitivity of the F1 and F2 generations to acetophenone was complemented by an enhanced neuroanatomical representation of the Olfr151 pathway. Bisulfite sequencing of sperm DNA from conditioned F0 males and F1 naive offspring revealed CpG hypomethylation in the Olfr151 gene. In addition, in vitro fertilization, F2 inheritance and cross-fostering revealed that these transgenerational effects are inherited via parental gametes. Our findings provide a framework for addressing how environmental information may be inherited transgenerationally at behavioral, neuroanatomical and epigenetic levels.
New research from Emory University School of Medicine, in Atlanta, has shown that it is possible for some information to be inherited biologically through chemical changes that occur in DNA. During the tests they learned that 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.
According to the Telegraph, Dr Brian Dias, from the department of psychiatry at Emory University, said: ”From a translational perspective, our results allow us to appreciate how the experiences of a parent, before even conceiving offspring, markedly influence both structure and function in the nervous system of subsequent generations.
“Such a phenomenon may contribute to the etiology and potential intergenerational transmission of risk for neuropsychiatric disorders such as phobias, anxiety and post-traumatic stress disorder.”
This suggests that experiences are somehow transferred from the brain into the genome, allowing them to be passed on to later generations.
1 December 2013
Experiments showed that a traumatic event could affect the DNA in sperm and alter the brains and behaviour of subsequent generations.
A Nature Neuroscience study shows mice trained to avoid a smell passed their aversion on to their “grandchildren”.
Experts said the results were important for phobia and anxiety research.
The animals were trained to fear a smell similar to cherry blossom.
The team at the Emory University School of Medicine, in the US, then looked at what was happening inside the sperm.
They showed a section of DNA responsible for sensitivity to the cherry blossom scent was made more active in the mice’s sperm.
Both the mice’s offspring, and their offspring, were “extremely sensitive” to cherry blossom and would avoid the scent, despite never having experienced it in their lives.
Changes in brain structure were also found.
“The experiences of a parent, even before conceiving, markedly influence both structure and function in the nervous system of subsequent generations,” the report concluded.