Before we can discuss how genes are expressed we need to first establish the difference between Genetics and Epigenetic. Genetics refers to the study of genes and their inheritance from one generation to the next, while epigenetic refers to the study of changes in gene expression that occur without changes to the underlying DNA sequence.
In other words, Epigenetic are the changes in gene expression caused by non-genetic factors such as environmental exposures and lifestyle factors like diet, stress, smoking, and aging
Epigenetic can be compared to a dimmer switch on a light. Just like how a dimmer switch can control the brightness of a light, epigenetic marks can control how strongly a gene is expressed. They can turn a gene up to full brightness or dial it down to a dimmer level, and this can affect how our cells develop and function.
What powers the epigenetic dimmer? One powerful force driving the changes to gene expression is Methylations.
Methylation is a chemical process that occurs in the DNA molecule, where a group of atoms called a methyl group is added to one of the DNA building blocks, called a cytosine. This process can change the way the DNA molecule is packaged in the cell and can affect how genes are expressed.
When a gene is methylated, the methyl group can act like a block to prevent the gene from being “read” and turned into a protein. This means that the gene is effectively turned off, or silenced. On the other hand, when a gene is not methylated, it is more likely to be read and turned into a protein, which means it is expressed.
Methylation is a key mechanism in epigenetics that helps regulate gene expression, which is important for many biological processes, such as cell differentiation and development. The pattern of methylation in a cell can also change over time in response to environmental factors, such as diet or exposure to toxins, which can affect the expression of genes and ultimately impact an individual’s health and disease risk.
In the metaphor of epigenetics as a dimmer switch, methylation can be thought of as a way of adjusting the level of gene expression. For example, when a gene is heavily methylated, it’s like the dimmer switch has been turned down, resulting in less gene expression. Conversely, when a gene is lightly methylated or not methylated at all, it’s like the dimmer switch has been turned up, resulting in more gene expression.
Just as a dimmer switch can be adjusted to find the right level of brightness, the degree of methylation on a gene can also be adjusted to find the right level of gene expression. This is important because different genes need to be expressed at different levels in different cell types and at different stages of development.
Epigenetics shows us that we have the power to impact our health and wellbeing beyond our genetic makeup. Environmental exposures and lifestyle factors like diet, stress, and exercise can change the expression of our genes through epigenetic marks like methylation. By understanding and harnessing the power of epigenetics, we can optimize our gene expression for proper cellular function and development, ultimately improving our health and reducing our risk of disease. This gives us hope and inspiration to take control of our health and make positive changes in our lives.