Our genetic code is the set of instructions in our DNA that carry the specific directions necessary to make proteins that help our body function. But how do these tiny differences in our genomes affect who we are and what we become? How do our genes and environment interact?
Scientists have found that what is actually important is how genes are regulated. This is what makes each one of us unique based on influences that lead to DNA changes in how certain genes can be activated or deactivated at different times. What may be new to many people is that the genes and environment interact and can play a prominent role in gene expression. There are even indications that these DNA changes in expression can be passed down to your offspring. This means that the experiences in your everyday life can cause changes in your DNA, which can be expressed in future generations.
Epigenetics Is the Science of DNA Changes in Gene Expression
Epigenetics describes the situation when there is no change to the DNA sequence, but there is a change in how the DNA is read. You can think of this as the mechanism that differentiates a nerve cell from a muscle cell, but this also includes environmental influence. What you eat, where you live, whether you smoke, how you exercise, and how much time you spend in the sun, are all factors that can cause chemical modifications based on the genes and environment that can turn the genes on or off.
A Scientific Explanation for How the Genes and Environment Talk
There are several ways in which this can be done. Inside the nucleus, DNA coils around bundles of proteins called histones. This forms chromatin, the material that chromosomes are made of. If you alter the structure of the chromatin, you will alter a DNA change in gene expression. Various chemical groups achieve this by either modifying the histone proteins or the DNA. Histone modifications include acetylation and methylation. This means that you can activate or repress gene expression. Acetylation adds an acetyl group onto the histone tails which will activate those genes. The removal of the groups will do the opposite and deactivate the gene. Methylation adds methyl groups to DNA and will typically block that gene, making it inactive. When the methyl group is later removed, the gene becomes active again.
The environment is playing a larger role in how our genes are expressed and people can have different gene expression based on their environmental exposure. Certain chemicals and radiation causes DNA damage and can affect how genes are expressed. Research is already ongoing for how these DNA changes can affect skin diseases like eczema and acne. A deeper understanding of genetics can tell you that we, to some degree, determine the state of our own health.