Do you remember when we eagerly awaited knowing the human genome, thinking we’d then understand all about how we were programmed to function? It was a bit embarrassing to learn that we have a similar number of genes to many mammals, and fewer than a lot of plants! Clearly genes don’t tell the whole story!!
Epigenetics help explain why our genes are not a simple
instruction manual for the human body.
Genes are made up of many pairs of only 4 basic building blocks, on a spiral backbone, resembling a twisted ladder. The order of these blocks forms a code that, when translated, builds a molecule we need. A gene only encodes for one molecule, usually a protein, but that molecule may then be involved in more than one task in your body, so each gene can affect multiple body systems.
Each cell contains your whole genome: all of your genes. If they were unraveled they’d be about 6 ½ feet, or 200 cm long. And all that is tightly curled up inside the nucleus of every one of your cells! Although every cell of your body contains the same DNA, different markers tell it whether to read the information on how to be a liver cell, how to make a hormone, or help form an eyelash. They do this by silencing the information that isn’t needed, making sure it isn’t read, like a document with many words crossed out.
Epigenetic markers fine-tune genetic expression, using chemical tags that may be applied or removed throughout a person’s life.
Epigenetics is the science that looks into how changes to the gene can alter how much it is expressed: why some codes are used a lot, some less, and some ignored altogether!
Here’s how it works: You can think of your genes like a library of information. Small chemicals attach to the genes: little “tags”, like bookmarks in a book. They tell your cells which genes to read, which to read a lot, and which not to read at all. So you want those bookmarks in all the right places!
Our lifestyle and our environment affect how our genes turn our genetic potential into our reality!
Yes, those bookmarks can be added or removed depending on what we consume, how much physical activity we do, what we are exposed to and what we experience. What’s more, they can then be passed down from one generation to the next. In one study mice passed an induced epigenetic sensitivity to a scent down three generations. In the third generation of mice, researchers proved that this inherited trait could be reversed.
This is an important mechanism explaining how a healthy lifestyle really does create a healthier body, deeply and profoundly, at the level of our genes.
Studies have also shown that good diet and exercise in pregnancy beneficially affect the epigenetics in the placenta and are passed on to the baby: it’s a healthy inheritance you can pass on to your unborn children.
These epigenetic changes can affect the likelihood that someone gets an illness, and if they do get it, how effectively they can recover from it. For example, epigenetic markers associated with unhealthy nutrition and environmental toxins have been found to contribute to the disordered metabolism of obesity, metabolic syndrome, fatty liver and Type 2 diabetes. The good news is that we know that these changes can be reversed!
Genes that affect more than one system may also help to explain some observed connections between diseases and lifestyle factors. For example, some genes that influence circadian rhythm also affect several metabolic functions, and multiple studies have shown a connection between sleep deprivation and obesity & type 2 diabetes.
MicroRNAs provide another mechanism for epigenetic effects. They help cells control the types and amounts of proteins they make, by slowing or preventing the process of expression of specific genes. And they, too, are affected by our lifestyle.
Are you asking yourself “How can I benefit my genome”?
Studies now show that a healthy lifestyle benefits you and your epigenome. Physical activity, adequate sleep and stress reduction, and nutrients like folate, polyphenols, phytoestrogens, and selenium, from a healthy diet, have all been shown to support healthier epigenetics.
Conversely, poor diet, excess alcohol consumption, environmental pollutants, cigarette smoking and even working night shifts, can have detrimental effects on your epigenome.
Epigenetics is a dynamic science, reflecting the interplay between your body and your environment. You can choose how you want to influence your genetic markers, and SHINE is full of ideas on to how to support this!