Your DNA May Put You at Risk of Diabetes, Heart Disease and Schizophrenia: New Study Explains Why

Most people may carry a high genetic risk of developing diabetes, cardiovascular disease and schizophrenia, even if they are currently healthy. However, this does not mean they will necessarily develop these conditions, according to a new study led by researchers at the University of Exeter in the UK.

Published in the journal ‘Genome Medicine’, the study analysed genetic data from nearly one million people to understand what a typical human genome looks like and how genetic variations influence disease risk.

What Did the Study Find?

Researchers examined data from two major population databases: the UK Biobank and the US-based All of Us research programme.

• They found that the average human genome contains around five million genetic variants.
•  These are differences in DNA that make each person genetically distinct.

Around 10,000 of these variants can alter gene sequences and may influence health, including lactose intolerance and how the body responds to medicines. However, many genetic variations have little or no harmful effect.

The researchers also found that every person carries around one to three rare genetic variants previously linked to serious inherited diseases. In addition, individuals carry approximately 50 rare variants whose clinical significance remains uncertain.

When the researchers assessed genetic risk scores for 28 common conditions, they estimated that the average person fell within the top 10 per cent of genetic risk for nearly three conditions. Around one in five people fell within the top one per cent for at least one condition.

These findings suggest that genetic variations associated with disease are common, even among people who may never develop those illnesses.

Does High Genetic Risk Mean You Will Develop a Disease?

Not necessarily. Having a genetic predisposition means a person may be more likely to develop a condition than someone with a lower genetic risk. It is not a definite prediction of future illness.

Polygenic risk scores combine information from multiple genetic variants to estimate a person's susceptibility to a disease. However, these scores cannot independently determine whether someone will develop a particular condition.

Several other factors influence health, including age, family history, diet, physical activity, smoking, environmental exposure, and existing medical conditions.

For instance, someone with a genetic predisposition to type 2 diabetes may reduce their overall risk through healthy lifestyle habits and appropriate medical care. Similarly, genetic susceptibility to cardiovascular disease does not mean a person will inevitably develop heart problems.

The researcher stressed the importance of interpreting genetic findings alongside symptoms, family history and other clinical and environmental risk factors.

Also Read: Genetics or Lifestyle, Which Matters More for Heart Disease?

Why Are These Findings Important?

As genetic testing becomes more widely used in healthcare, understanding what test results actually mean is increasingly important.

A report identifying a disease-associated genetic variant can cause unnecessary worry if it is interpreted without proper medical guidance. Some variants may never cause illness, while others require further assessment to understand their significance.

The findings could help healthcare professionals interpret genetic test results more accurately and provide better guidance to patients considering genetic screening.

However, the researchers also highlighted an important limitation: the databases used in the study included a disproportionately high number of people of Western European ancestry. More diverse genetic data are needed to understand how these findings apply to populations worldwide, including Indians.

What Should You Do to Protect Your Health?

Genetics is only one part of the health picture. Although some inherited risks cannot be changed, several lifestyle factors can be managed.

Eating a balanced diet, exercising regularly, maintaining a healthy weight, avoiding tobacco, getting adequate sleep and attending recommended health screenings can support long-term health.

People with a strong family history of diabetes, heart disease or other inherited conditions should discuss appropriate screening and preventive measures with their healthcare professional.

Final Word

Genetic risk is not the same as a diagnosis. Understanding your genetic background can help guide prevention, but your health cannot be predicted by DNA alone.