Does epigenetics open up the whole ‘nature vs nurture’ debate? This article is a very clear (yet detailed) explanation of the compelling evidence that life experiences can actually change our genes and therefore affect the inheritance of traits and dispositions.
Two scientists walk into a bar – no this is not a joke! It happened in 1992. The bar was in Madrid, Spain and the scientists were Moshe Szyf, a molecular biologist and geneticist and Michael Meaney, a neurobiologist. By the time they left that bar the world of the natural and human sciences was potentially changed forever.
A key question arose from that first fateful meeting “If diet and chemicals can cause epigenetic changes, could certain experiences — child neglect, drug abuse or other severe stresses — also set off epigenetic changes to the DNA inside the neurons of a person’s brain?” Through the research that ensued it was proved that a change in the diet of lab animals not only changed their physiology, but that these changes could then be transmitted to their offspring via their genes.
This article goes on to say that your early or formative experiences in life can change the DNA in your brain and form your emotional profile and that these environmentally caused dispositions can then be passed on to your children genetically. “Your parents winning the lottery or going bankrupt when you’re 2 years old will likely affect the epigenome of your brain, and your resulting emotional tendencies, far more strongly than whatever fortune finds you in middle age.”
The process of behavioural epigenetics revolves around the way methyl groups are attracted to the outer coating (histones) of chromozomes and thereby “marking” various parts of code that are then transcribed to core DNA.
This process is sometimes known as postnatal inheritance.
The key questions listed at the end of this article point to ethical issue of tampering with this process to free us from negative forms of epigenetic inheritance.
- How could we be sure that epigenetic drugs would scrub clean only the dangerous marks, leaving beneficial — perhaps essential — methyl groups intact?
- What if we could create a pill potent enough to wipe clean the epigenetic slate of all that history wrote?
- If such a pill could free the genes within your brain of the epigenetic detritus left by all the wars, the rapes, the abandonments and cheated childhoods of your ancestors, would you take it?
The other questions is – how do these ideas sit with the idea of the Sebastian Seung’s ‘connectome’.
Read full article in ‘Discover’ magazine here