When Rene Descartes, the influential 17th century French philosopher, famously said, “I think, therefore I am,” he wasn’t referring to the science of epigenetics, but his quote could be a mantra for this emerging field of study.
What is Epigenetics?
Epigenetics is defined as “the study of changes in organisms caused by modification of gene expression rather than alteration of the genetic code itself;” in other words, although the environment or one’s experiences don’t alter the genetic code, they do alter the way cells read the genes and how they behave as a result.
Kidshealth.org explains it more simply, saying that the idea that the environment and life experiences “can change the health not only of the people who are exposed to them, but also the health of their descendants, is something we’ll be hearing more and more about.”
Study of Epigenetics
Researchers have shown that environmental circumstances can cause genes to be switched on and off and passed down with the switching mechanism set in the same position, so that offspring show a trait that is the result of something they never experienced themselves.
For example, researchers looked at people residing in the western portion of the Netherlands during 1944-45 when they were blockaded by the Nazis. Food became extremely scarce and people rationed their food, sometimes living on as little as 580 calories daily. More than 22,000 people starved to death during this period.
In examining the children born during this time, researchers found that they were underweight and disease prone. Even more interesting, however, was the finding that the children of these children were underweight at birth, even though they hadn’t been nutritionally deprived while in the womb. However, a genetic switch had been triggered.
These on-off mechanisms can affect such conditions as mental illness, obesity, memory and addiction. Recently, a team of Israeli researchers at the University of Tel Aviv discovered that the mechanism responsible for the ability of a gene to switch on or off is a small bit of RNA. Their work, done with worms, has “revealed an active, tunable inheritance mechanism that can be turned ‘on’ or ‘off.’ ”
“These switches are controlled by a feedback interaction between gene-regulating small RNAs, which are inheritable, and the genes that are required to produce and transmit these small RNAs across generations,” Professor Oded Rechavi told Wired magazine. “The feedback determines whether epigenetic memory will continue to the progeny or not, and how long each epigenetic response will last.”
Epigenetic Alteration and Your Offspring
Although a number of epigenetics studies have focused on examining inherited tendencies toward illness, other studies are exploring the positive opportunities we have to influence our genetic makeup and that of future generations.
MedicalDaily.com reported on a Duke University study that homed in on the pre-natal nutrition by implanting embryo clones into mice, which were then given differing diets. The baby mice varied in weight, fur colour and risk for chronic disease, depending on what the mothers had eaten. Nutrition also affected their own sperm and egg cells.
Epigenetic Inheritance Can Be Altered
Turning on genetic switches can have positive effects. In a study conducted by Dr. Linda E. Carlson, results showed that meditation could have an impact on the lifespan of breast cancer survivors. She divided the survivors in her study into three groups: one group took part in meditation and yoga; another in group therapy; and the third took a short-term stress management course.
Those who meditated and did yoga and those who underwent group therapy were able to preserve the length of their telomeres, the caps on chromosomes that prevent them from deteriorating and leading to ill health. Telomere length preservation was absent in those who studied stress management, so meditation and therapy have beneficial effects on the genes.
Epigenetics and Meditation
A study out of the University of Wisconsin also demonstrated the impact of meditation on human molecular composition. Among the molecular changes noted in those who had meditated, researchers found “altered levels of gene-regulating machinery and reduced levels of pro-inflammatory genes, which in turn correlated with faster physical recovery from a stressful situation.”
The researchers said that there was no difference between the tested genes in the two groups prior to the start of the study, indicating that the meditation led to epigenetic alterations to the genome.
“Our genes are quite dynamic in their expression and these results suggest that the calmness of our mind can actually have a potential influence on their expression,” said Professor Richard Davidson, an author of the study.
Wouldn’t it be exciting to change not only your genetic destiny, but that of your offspring and your offspring’s offspring? Not meditating yet? It’s easier than you think.