Scientists are definitely not in agreement about whether it is environment or genetics that influence what goes on in our brains, and our bodies. Some believe that we are what came before us, and that our ancestors pass down our genetic markers, which include diseases and conditions our bodies go through. Others believe that it is our environment that influences the way we think, act, react and even our medical problems.
As we learn more and more about neuroscience, how the brain works, the more scientists are finding they can be both right and wrong. It seems that more evidence is piling up every day that it is a combination of both nature and nurture, that we are affected by what came before us, and what is going on around us.
Our diets and lifestyle can change the way our genes express themselves by influencing a network of chemical switches within our cell, known collectively as the epigenome. From this new understanding scientists may be able to lead to therapies for cancer and other disease, and possibly stop us from passing down the predisposition to our children and their children.
A study conducted in a remote community in northeastern Sweden, called the Överkalix study, studied genetic imprinting and the physiological effects from environmental factors that could have been passed down through the generations. The scientists studied historical records and charted time lines and other data when food was plentiful, and when there were periods of famine. Överkalix made the perfect control group to study since the community was isolated and most of the people born there stayed and raised their children.
They studied 303 people — 164 men and 139 women born in 1890, 1905 and 1920. They also studied records of their 1,818 parents and grandparents. in 1995, when the study ended, 44 were still alive. The rate of death for the children and grandchildren was found to correlate with the times of available food supplies in the historical data they put together.
Marcus Pembrey and his colleagues found in the Överkalix study that the paternal grandsons of Swedish men (but not maternal) who were alive during periods of famine in the 19th century showed less likelihood for cardiovascular disease. They also found the grandchildren of the descendents of those who lived through prosperous times had an increased incidence of death from diabetes.
Interestingly, the opposite was true for female descendents of paternal (but not maternal) women who experienced famine while in the womb (while the eggs were being formed). They were found to live shorter lives than the average.
Many genetic imprints have been found to be associated with human disorders, such as Prader-Willi syndrome or Angelman syndrome, sister disorders that basically differ depending on whether the genetic chromosome mutation is inherited from the mother’s or father’s side of the family.
Another example is that of identical twins, who start out looking alike but end up different. According to a Duke University study, the genome is like a computer, the software that tells the cells to work or not. The epigenome are what change as we grow, especially during puberty or pregnancy. They change due to what we eat, the different air we breath, illnesses we get, stress levels and other things that happen around us. We pass these experiences down to our children, and they pass them along to their children.
The Duke scientists studied cells from 40 pairs of identical twins between the ages of 4 to 56. As they aged their genomes changed considerably, especially when their lifestyles were different.
Neuroscience has indicated that your genes, by themselves, are not your destiny. While genetic DNA provides the blueprint for every genetic instruction in your body, when and how genes are expressed seems to matter most. The science of how your genes are regulated — turned on and off, volume level raised or lowered… but without changing the DNA itself — is known as epigentics.
We can change our genetic imprinting for future generations. The Journal of Neuroscience published a paper showing that even memory – a wildly complex biological and psychological process – can be improved from one generation to the next via epigenetics. In the study by Tufts University, mice were implanted with genetic memory problems and then placed into an environment full of toys, allowed lots of exercise, and given extra attention. They demonstrated significant improvement in a long-term form of neural transmission that is key to memory formation. Amazingly, their offspring also showed the same improvement, even when the offspring got no extra attention.
About the author:
Ron White is a two-time U.S.A. Memory Champion and memory training expert. As a memory keynote speaker he travels the world to speak before large groups or small company seminars, demonstrating his memory skills and teaching others how to improve their memory, and how important a good memory is in all phases of your life. His CDs and memory products are also available online at BrainAthlete.com.
Sources:
Memoryzine.com – Worried About Your Parent’s Memory Problems, And You’re Next In Line? Nature vs Nurture….. Meet Epigenetics! – http://memoryzine.com/2010/12/11/worried-about-your-parent%E2%80%99s-memory-problems-and-youre-next-in-line/
Wikipedia — Epigenetics: http://en.wikipedia.org/wiki/Epigenetics
Nova – PBS video Aired July 24, 2007 — Epigenetics: http://www.pbs.org/wgbh/nova/body/epigenetics.html
