When you hear the phrase DNA testing, the majority of people will think of paternity testing.

However, medical advances now mean genetic testing can be carried out for a number of reasons including determining your risk of developing a disease like cancer or Alzheimer’s. Simple blood tests can now identify people who are more likely to suffer from certain health problems in the future.

But researchers at Cambridge University have found that most people will not act on the results of these genetic tests. A study discovered that when people are told they are at a high risk of developing a disease or condition, they simply accept their fate rather than take steps to change their lifestyle.

The research, which has been published in the British Medical Journal, looked at the results of 18 previous studies which had involved 6,000 people.

In the past, medical professionals had believed that people who had been told their genes made them likely to develop a disease would make changes to the way they lived to try to reduce their chance of becoming ill. However, researchers found people largely ignored professional advice about exercise, diet and smoking.

Those told they were high risk were also no more likely to take part in a screening programme than anyone else.

New approach needed to encourage lifestyle changes

The research team, which also includes scientists from Imperial College London and the University of Manchester, suggested doctors might need to change their approach.

Professor Theresa Marteau, study leader and director of the Behaviour and Health Research Unit at Cambridge, said: “Expectations have been high that giving people information about their genetic risk will empower them to change their behaviour – to eat more healthily or to stop smoking, for example – but we have found no evidence that this is the case. But nor does the evidence support concerns that such information might demotivate people and discourage them from changing their behaviour.”

Genome sequencing allows an individual’s DNA to be examined to see if it contains genes which increase their risk of diseases like cancer and heart disease.

And Dr Gareth Hollands, co-author of the report, said that DNA testing still has a valuable role to play in modern medicine.

He said: “DNA testing, alone or in combination with other assessments of disease risk, may help clinicians identify individuals at greatest risk and allow them to target interventions such as screening tests, surgery, and drug treatments.”