Good question. It is interesting to consider whether past trauma can affect current and future generations. The tricky part would be to prove that trauma from centuries ago was the single factor that directly affected the DNA expression of the present generation.

One component to consider is the genetic diversity that exists within a single society. People from the same community can have different versions of the same gene. Therefore, they may react differently to the same experience – including the effect on their DNA.

It would be interesting to see if the link you’re asking about exists. Another point to bear in mind is the ability to differentiate between genetic alterations that are passed on from generation to generation, versus environmental factors. A community-wide traumatic event could have affected how future generations were raised. Perhaps the incident itself changed the environment (eg, addition of chemicals). Separating the effect the environment on DNA expression from the effect of the event itself would be complicated. If future generations moved, the same quandary exists. The stress of relocating alone can be a confounding factor.

Moreover, even if a traumatic experience affected and altered someone’s DNA expression, such a change would only be passed onto future generations if it occurred in the reproductive cells.

If you are interested, the below link leads to the U.S. National Cancer Institute’s index of slides explaining genetics (link #11 explains hereditary mutations):

http://www.cancer.gov/cancertopics/understandingcancer/genetesting

Recently, a noteworthy article was published by the Harvard School of Public Health. It links a woman’s childhood abuse to an increased risk of having autistic children. However, even those researchers warn that they did not prove cause-and-effect. Regardless, the research is interesting. Here is a link to an article summarizing the research:

http://ca.news.yahoo.com/women-abused-children-more-likely-kids-autism-105634295.html

Hopefully this has provided you with a good starting point to further delve into the topic. Glad to see that you’re finding the research thought-provoking.

Also are there any researchers looking into trauma that occurs within a civilization or a race of people?

what do you think?

Thanks for responding and for being helpful.
You have given me enough to start with and again I thank you for posting all this.
Have a great xmas and all the best for the new year.

Of course, I’d be happy to provide more materials for you to read. Glad this has piqued your interest in the subject area.

Here is a link to the original publication of the research. It’s the website of the peer-reviewed journal that this research was published in (one of the top research journals in the world). Unfortunately, due to copyright reasons, a copy of this work must be purchased to be read (and I am not permitted to distribute it for free). However, you can still read the abstract (free of charge) and in case you’re interested in more, you always have the option to purchase a full copy:

http://www.nature.com/neuro/journal/vaop/ncurrent/full/nn.3275.html

Another site you might want to take a look at is that of the Max Plank Society. This is the link to their news release about this research:

http://www.mpg.de/6643282/childhood-trauma-dna

Since you sound so curious, here’s another link that you might enjoy. It’s an older article written a few years ago (for a general audience) that discusses the link between FKBP5 gene variants and mental illness (but not the effect of childhood trauma on gene expression since this article predates the discovery):

http://www.psychologytoday.com/blog/mouse-man/200811/gene-anxiety-depression-and-posttraumatic-stress-disorder-fkbp5

Happy reading!

Thanks for your further explanation.Raises a whole bunch of more questions of course.
It is an interesting subject and the beginnings of further studies in a relatively new field of
DNA concerning cause and effects, particularly in Child Physchology. Do you have any other links or references to this research and/or the FKBP5 Gene? Thanks for your post(s).
P.S.I don’t think Benjamin Franklin would have
discovered anything without curiousity, not to mention Thale,Gray, and a few others before him.

Glad to see that you’re curious to learn more. The so-called “mute button” is actually a methyl group that is supposed to be permanently attached to a DNA base on everyone’s FKBP5 gene (essentially, the default is to prevent this gene from overreacting).

This study examined the most traumatic situations possible (i.e. abuse). However, researchers have yet to investigate or find a so-called threshold with respect to stressful situations. A lot more research would be required. The likelihood of having your DNA altered by stress would also depend on a person’s genetic makeup. The number of people affected depends on the percentage of those who are at risk (i.e. who carry a specific version of this gene). A predisposition would increase the chances of having this methyl group literally break off the DNA base under the aforementioned circumstances. The only method to measure whether or not you are a) predisposed or b) have lost this methyl group is through DNA analysis as conducted by these researchers.

In terms of population, this study only examined individuals of African-American descent. Since genes are inherited, any numbers from this study (with respect to likelihood of having this gene variant and increased risk) would only be relevant to that subsection of the population. More research would be required before scientists would feel comfortable making a blanket statement with regards to the general population. It is also worthwhile to note that any abuse leads to a higher risk of developing mental illness later on in life. There are many other genes involved in our stress response. Some of these may also be affected, to varying degrees, by trauma.

As is often the case with research, any new discovery leads to many more questions. It definitely keeps things interesting.

The fact that a psychological state can alter your DNA is a huge discovery. This is just the first step.

Your statement is like saying, Benjamin Franklin discovering electricity is useless because he couldn’t use it right away.