Our life experiences may be
passed on to our children and our children's children - and now scientists
report that they have discovered that this inheritance can be turned on or off.
Epigenetics is the study of inherited changes in gene expression, changes that
are inherited, but aren't inherent to our DNA. For instance, life experiences,
which aren’t directly coded in human DNA, can actually be passed on to
children. Studies have shown that survivors of traumatic events may have
effects in subsequent generations. The question, of course, is how are these
genetic 'memories' passed on and this is what a Tel Aviv University (TAU) was
seeking to answer when they reportedly discovered a mechanism that makes it
possible to turn the transference of environmental influences on or off.
According to their study,
epigenetic responses that are inherited follow an active process as it gets
passed on through generations. They showed that worms inherited small RNAs
following the starvation and viral infections of their parents. These small
RNAs helped prepare their offspring for similar hardships. They also identified
a mechanism that amplified heritable small RNAs across generations, so the
response was not diluted. They found that enzymes called RdRPs are required for
re-creating new small RNAs to keep the response going in subsequent generations.
Scientists were able to determine that specific genes, which they dubbed
Modified Transgenerational Epigenetic Kinetics (MOTEK) are also involved in
turning epigenetic transmission on and off.
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