Genetic risk factors for type 2 diabetes
Scientific support: Prof. Dr. Johannes Beckers
The risk of developing type 2 diabetes is made up of several factors. The hereditary factor plays a crucial role. There are numerous known genetic characteristics that encourage the onset of metabolic diseases.
Although, with the gene you only inherit a predisposition for type 2 diabetes and not the actual disease. You can develop type 2 diabetes during your lifetime even without having an inherited predisposition.
Whether a predisposition actually results in the onset of type 2 diabetes generally depends on external factors, such as lifestyle. In this context, diet, physical activity, and being overweight are the central factors.
Contents
- Is type 2 diabetes hereditary?
- What are genes and what is epigenetics?
- What role do environmental and lifestyle factors play in the onset of type 2 diabetes?
- What can you do when you are at increased risk of type 2 diabetes?
- Do exercise and diet have different effects on diabetes prevention?
- Will type 2 diabetes treatment focus more on genetics in the future?
1. Is type 2 diabetes hereditary?
There are a number of causes involved in the onset of type 2 diabetes. One of these is the inheritance of genetic characteristics. Scientists have identified more than 100 genetic loci that are associated with type 2 diabetes. The predisposition for type 2 diabetes can be passed from one generation to another via the genes.
Compared to someone with no familial predisposition, people whose mother or father have type 2 diabetes are approximately 1.7 times more likely to develop type 2 diabetes during their lifetime. If both parents are affected, then the risk is almost 3 times higher.
However, type 2 diabetes does not develop solely as a result of genetic predisposition. It only develops when other lifestyle factors come into play alongside genetic predisposition. These include lack of physical exercise, obesity and/or an unhealthy diet.
Lifestyle factors can affect the activity of the genes responsible for sugar metabolism. These are known by researchers as epigenetic factors and they modify the risk for developing type 2 diabetes.
Good to know:
Alongside predisposition, environmental factors and habits play a role in the onset of type 2 diabetes. And: Type 2 diabetes can also develop without a hereditary predisposition.
2. What are genes and what is epigenetics?
Genes contain the hereditary information that determines the “blueprint” of a person. For example, the genes determine what hair, skin, or eye color a person will have. This information that is read by the genes and then transformed into proteins is also responsible for metabolic function and other functions of the body.
The field of Epigenetics is a young branch of research that focuses on the correlation between the non-modifiable hereditary information contained in the genes and modifiable external factors. External factors include your lifestyle (e.g., physical activity and dietary habits). These can have epigenetic (meaning “on top of” or “in addition to” genetics) influences.
Epigenetic influences chemically modify genetic activity. These modifications dictate how strongly or weakly genetic information is able to be read and implemented in the body. When genes responsible for the metabolism are affected, this can facilitate or – depending on the type of epigenetic influencing factors – prevent the onset of type 2 diabetes.
Good to know:
Lifestyle affects every aspect of sugar and fat metabolism. Certain lifestyle factors cause changes in the reading of metabolism-relevant genes via epigenetic mechanisms.
3. What role do environmental and lifestyle factors play in the onset of type 2 diabetes?
An important discovery in recent years was epigenetic factors can be inherited as well as genes. Using a mouse model, scientists were able to show that diet-induced type 2 diabetes was passed on to descendants via the ova and sperm cells by means of epigenetic mechanisms.
Although the hereditary information on the gene itself cannot be modified, the epigenetic factors can be actively influenced. This is possible using lifestyle adjustment. Researchers assume that a lifestyle with a healthy diet and sufficient physical activity can have a positive influence on the epigenetic factors in many of those affected.
Good to know:
During testing of genetically predisposed people, the risk of type 2 diabetes was reduced in some cases using a change in diet and increased physical activity.
However, individual differences do exist: Not all people with an elevated risk of type 2 diabetes respond equally as well to different lifestyle changes.
4. What can you do when you are at increased risk of type 2 diabetes?
If there is an elevated familial risk of type 2 diabetes or initial changes to the sugar metabolism have become evident, those affected can try to actively counteract this. A lifestyle adjustment can often prevent or, at least, delay the onset of type 2 diabetes.
The following are examples of measures to reduce your risk of developing type 2 diabetes:
Good to know:
Regular exercise should focus primarily on endurance (e.g., 10 minutes of brisk walking per day), strength (e.g., push-ups or squats), and coordination.
5. Do exercise and diet have different effects on diabetes prevention?
Scientists have discovered that lifestyle changes do not affect all people in the same way. For example, for one person, adjusting dietary habits is very effective while another may react more to physical activity.
Therefore, research is increasingly focusing on the range of genetic and epigenetic characteristics that influence how the individual metabolism reacts to food and physical activity.
Scientists are working on classifying people into different risk groups to better tailor individual measures for the prevention of type 2 diabetes. The aim is to find out what type of diet or lifestyle is particularly effective for each individual.
6. Will type 2 diabetes treatment focus more on genetics in the future?
Genetic and epigenetic characteristics play a crucial role in the risk of developing type 2 diabetes. In the future, new findings in these fields may help to better prevent type 2 diabetes using preventative approaches and treatment and by offering tailored medical treatment to those already affected.
The aim is to find tailored individual type 2 diabetes prevention strategies for those with an inherited increased risk. This is to prevent the onset of the disease during their lifetime. Those already suffering from type 2 diabetes should also benefit from a more precise application of therapeutic options.
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As of: 25.01.2022
