Hereditary trauma and the characters in your story
|Credit: Image by Isabelle Mansuy / UZH / Copyright ETH Zurich|
One thing I enjoy about writing fiction is working out the back stories of characters before I throw them into situations for the pure pleasure of seeing how they respond. It's especially pleasant when a minor character, all on their own, steps forward and takes over a story.
The importance of back story cannot be stressed enough, not just for you the writer, but for the reader. Constructing a back story, even if 90% what you build never appears in your story, keeps you and your characters consistent.
I learned this some years ago in a seminar taught by comedy legend Danny Simon. He stressed that what makes a joke funny is that it is character based. One of his tenets was that a character must behave consistently with their personality, whether funny or serious. If it's not consistent with who they are, it distracts the viewer or reader who wonder, "Huh?" and put your story down.
So it follows that the better you understand why people in general behave the way they do, the more consistent and believable your characters will be, no matter what the genre'. Make sense?
In most literature, characters experience or have experienced some sort of trauma. Trauma can drive story and conflict. To my surprise, a recent study published just this past week details how trauma not only makes psychological changes to a character, these changes can be passed from generation to generation in the form of physical changes RNA inherited by the child. Sort of a sins of the father sort of thing.
I hope this little tidbit helps as you develop your characters as a way of explaining who they are and why they do what they do - even if you never reveal this to your reader or viewer.
Traumatic experiences can induce behavioral disorders
that are passed down from one generation to the nextExtreme and traumatic events can change a person -- and often, years later, even affect their children. Researchers have now unmasked a piece in the puzzle of how the inheritance of traumas may be mediated. The phenomenon has long been known in psychology: traumatic experiences can induce behavioral disorders that are passed down from one generation to the next. It is only recently that scientists have begun to understand the physiological processes underlying hereditary trauma
"There are diseases such as bipolar disorder, that run in families but can't be traced back to a particular gene," explains Isabelle Mansuy, professor at ETH Zurich and the University of Zurich. With her research group at the Brain Research Institute of the University of Zurich, she has been studying the molecular processes involved in non-genetic inheritance of behavioural symptoms induced by traumatic experiences in early life.
Mansuy and her team have succeeded in identifying a key component of these processes: short RNA molecules. These RNAs are synthesized from genetic information (DNA) by enzymes that read specific sections of the DNA (genes) and use them as template to produce corresponding RNAs. Other enzymes then trim these RNAs into mature forms. Cells naturally contain a large number of different short RNA molecules called microRNAs. They have regulatory functions, such as controlling how many copies of a particular protein are made.
Small RNAs with a huge impact
The researchers studied the number and kind of microRNAs expressed by adult mice exposed to traumatic conditions in early life and compared them with non-traumatized mice. They discovered 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. These alterations resulted in mis-regulation of cellular processes normally controlled by these microRNAs.
After traumatic experiences, the mice behaved markedly differently: they partly lost their natural aversion to open spaces and bright light and had depressive-like behaviors. These behavioral symptoms were also transferred to the next generation via sperm, even though the offspring were not exposed to any traumatic stress themselves.
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The metabolism of the offspring of stressed mice was also impaired: their insulin and blood-sugar levels were lower than in the offspring of non-traumatized parents. "We were able to demonstrate for the first time that traumatic experiences affect metabolism in the long-term and that these changes are hereditary," says Mansuy. The effects on metabolism and behaviour even persisted in the third generation.
"With the imbalance in microRNAs in sperm, we have discovered a key factor through which trauma can be passed on," explains Mansuy. However, certain questions remain open, such as how the dysregulation in short RNAs comes about. "Most likely, it is part of a chain of events that begins with the body producing too much stress hormones."
Importantly, acquired traits other than those induced by trauma could also be inherited through similar mechanisms, the researcher suspects. "The environment leaves traces on the brain, on organs and also on gametes. Through gametes, these traces can be passed to the next generation."
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Story Source: Materials provided by ETH Zurich. Gapp K, Jawaid A, Sarkies P, Bohacek J, Pelczar P, Prados J, Farinelli L, Miska E, Mansuy IM. Implication of sperm RNAs in transgenerational inheritance of the effects of early trauma in mice. Nature Neuroscience, April 13, 2014