What Are Genetic Markers and What Are They For?

A genetic marker is a DNA sequence that helps us in the study of hereditary diseases. Today, we'll tell you what you need to know about genetic markers.
What Are Genetic Markers and What Are They For?
Elisa Martin Cano

Written and verified by the doctor Elisa Martin Cano.

Last update: 27 May, 2022

These days, continuous scientific progress helps us to better understand the causes and characteristics of many diseases or individual traits. Thanks to these advances, science has identified genetic markers. And, as a result, we can learn more about diseases and their prevention. So, what’s a genetic marker, and what’s it for? In the following article, we’ll tell you what you need to know.

What are genes?

First of all, genes are segments of DNA that pass on from parent to child and contain basic information about how the cell should function. These genes are responsible for making each individual the way they are, both inside their organism and in their appearance.

Genes make up part of chromosomes, which is the organizational structure of our DNA. These chromosomes, in turn, are located in the nucleus of each cell. That’s to say, all the cells of our body have the same genetic material in their nucleus and this will give the instructions to function. We know the set of genes as the genome.

In addition, each person’s genetic information will be unique. The combination of maternal and paternal genes will determine it. Each gene can have many variations among different people and, in addition, mutations can occur in them.

A doctor holding a floating image of a DNA strand.
Each person’s genetic information will be unique, depending on the combination of maternal and paternal genes.

What’s the importance of genes?

Although their importance is vital and, as we’ve already said, they control all the functions of the body, we’ll focus on their role in the development of diseases. Studies have shown that there are many diseases that are hereditary.

This means that the information for a person to develop a certain disease is present in the genes and that parents will transmit it to their children. The cause of a disease is usually a mutation in some gene, which leads to an alteration in the function it controls.

Therefore, knowing which genes cause a disease and their different mutations will allow us to know if a person is at risk of developing a certain disease. It’ll also let us know more about the general characteristics of that disease.

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What are genetic markers?

As we’ve already mentioned, the advance of technology and science has been a determining factor in the discovery of genetic markers. A genetic marker is a fragment of DNA whose exact position in the genome scientists are aware of.

Each marker is associated with a specific trait of a disease. Genetic markers are useful both to establish a person’s risk of developing a disease and to study the different versions of a gene in different individuals and populations.

There are genetic markers that are, in themselves, contributors to the development of diseases. Others simply tend to be inherited along with the genes we’re interested in for a certain disease and are located in close proximity to them.

Damaged DNA.
Genetic markers are associated with a specific disease trait.

What’s a genetic marker for?

Experts believe that a person’s DNA pool contains more than 30,000 genes that encode different substances and bodily functions. It’s true that there are now techniques that scientists can use to sequence the entire genome of each individual. However, this remains a costly, time-consuming, and often unhelpful procedure.

Most of the time, in the study of these hereditary diseases, scientists aim to study those genes and their varieties whose relationship with the disease in question they’re already aware of.

Genetic markers, therefore, will allow us, by knowing their exact position in the genome, to directly study the genes that interest us without having to study the complete DNA of a person.

Genetic markers: What should be clear?

Every day, there are more and more scientific advances and discoveries, as well as the development of very sophisticated technologies. The use and knowledge of these genetic markers are among them.

Over time, we’ll gain greater knowledge regarding the relationship between specific genes and hereditary diseases. And these markers will help us to study them in each person who requires them.


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This text is provided for informational purposes only and does not replace consultation with a professional. If in doubt, consult your specialist.