What Is DNA Methylation In Epigenetics?

Longevity 120 is a community-supported website. We may earn a small commission on purchases made through our links. Learn more.

DNA methylation is an epigenetic process that has its applications in gene expressions and modifications. In general, epigenetics tends to deal with how the environment, as well as your own behaviour and actions, can impact how your genes function.

There are several things that are important to know about DNA methylation, such as what it is, how it works and how this process can impact the way our genes and bodies function. You can learn all about these aspects in the following sections.

First, however, let’s take a brief look at what epigenetics is.

What Is Epigenetics?

Epigenetics is a field of study that falls under biology. This field tends to focus on the combination of genetic and environmental functions. In particular, epigenetics studies how the environment and how you react to and behave in the environment can have an impact on your genes and how they function.

The changes that the environment or the cells can control gene activity are referred to as epigenetic changes. You should note, however, that these changes are not necessarily permanent or irreversible. They can, in fact, be reversed quite easily.

There is, therefore, no alteration when it comes to the entire DNA sequence itself. Instead, your body undergoes changes in terms of absorbing and reacting to such modifications. The alteration, therefore, is in the gene expression and not the structure itself.

Protein production in the cells undergoes changes as a result of this process. Some environmental aspects that can result in this kind of change or modification include your diet, lifestyle, habits, pollutants, growth, aging and more.

There are several kinds of epigenetic changes that include DNA methylation, histone modification and non-coding RNA (ribonucleic acid).

What Is DNA Methylation And How Does It Work?

DNA methylation is one of the changes that take place when it comes to the expression and function of the genes. The cells make use of this process to control and regulate gene expression by turning certain kinds of gene expressions “off”.

Generally, one tends to inherit this kind of DNA methylation due to various cell divisions that may take place. This tends to be a highly dynamic process that tends to take place at different levels depending on the cells involved.

So, what exactly is it that occurs in the mechanism involved in DNA methylation? What changes take place here and why?

One of the first things you should know here is that the DNA comprises the following molecules or nucleotides as part of its structure or strands.

  • Cytosine
  • Guanine
  • Thymine
  • Adenine

In the process of DNA methylation, an additional methyl or CH3 group gets added to the strand, which can end up changing how the gene expresses itself in the body, often resulting in several kinds of changes that can then get inherited by succeeding generations.

Usually, this methyl group tends to get added to the cytosine ring, particularly at the fifth carbon atom through the occurrence of a covalent bond that involves the atoms sharing the electrons between them to complete their formation.

As a result of this kind of methylation, the cytosine in the DNA ends up getting transformed into what is known as 5-methylcytosine (or 5mC). To aid this process, some DNA-modifying enzymes called the DNA methyltransferases act on the conversion as well.

This can not only result in gene silencing but can also interrupt the process of transcription that is responsible for the copying of information from a DNA strand to an RNA molecule. This kind of copying and replication can then change the gene expression in generations that follow, provided that the conditions also support this.

DNA methylation, or the resulting 5-methylcytosine, is not abundant and is actually only present in around 1.5% of genomes, more commonly where the cytosine and guanine molecules occur one after the other.

However, there are still certain locations in cells that might feature this kind of consequence even without the consecutive occurrence of the cytosine and guanine.

Essentially, whenever this process takes place, methylation ends up altering the regular gene expression and results in inhibiting or turning the expression off. This can then result in several important consequences and impacts on the body and how it deals with various conditions and diseases.

What Impact Does It Have?

It is clear by now that DNA methylation involves the addition of a methyl group to the DNA strand that can then result in gene inhibition, stopping the expression of the gene from taking place as it usually would. When this happens, it can mean several things for the DNA sequence and the body.

For instance, DNA methylation can lead to several chronic and harmful conditions such as cancer, lupus, muscular dystrophy, nervous disorders, cardiovascular diseases, atherosclerosis and others.

This can then result in fatal gene expressions in the body that might prevent it from fighting against these dangerous cells, causing the conditions to develop further.

However, by correctly identifying this kind of occurrence in the DNA, it can become possible to take actions such as carrying out the process of DNA demethylation or getting rid of the methyl group from the DNA sequence.

Carrying out proper profiling and then taking steps to prevent the further growth of conditions (such as tumors) can help prevent the disease from worsening and resulting in death.

Other kinds of treatment options and therapies can also develop, although research surrounding these is still ongoing and can take some time to become widely applicable.

In many cases, however, you should note that DNA methylation can also serve to be useful for positive and active growth and development patterns, in which case demethylation can end up causing the problem.

What Is DNA Methylation In Epigenetics? The Bottom Line

To sum up, DNA methylation is an important process and type of epigenetics that can end up changing the gene expression by turning the signal off. This mainly takes place due to the addition of the methyl group to the DNA strand, especially to the cytosine molecule.

When this kind of process occurs, it can result in the development of healthy mechanisms or dangerous conditions. Research to deal with these is being developed.

Rosemary Richards