Communicating the results of DNA tests to patients has "little or no impact" on their unhealthy lifestyles, a new study has found.
Researchers analysed the results of 18 studies looking at the effects of communicating genetic risk estimates of heart disease, cancer and Alzheimer’s disease.
In each instance, behavioural change - such as quitting smoking, stopping drinking or doing more exercise - could reduce a person's risk of developing health issues.
They found that communicating DNA-based risks for these behaviours did little in prompting people to change their ways.
The study also found that there were no effects on other behaviours such as alcohol use, medication use, sun protection behaviours and attendance at screening or behavioural support programmes.
The research team, led by Professor Theresa Marteau at the University of Cambridge, said the results are particularly timely as people are becoming more interested in personalised medicine and increasing use of direct-to-consumer testing for a range of common complex disorders.
The findings were published in the British Medical Journal on 15 March.
Researchers said current studies in the field were at "risk of bias" and evidence was typically of low quality.
They concluded: "Existing evidence does not support expectations that such interventions could play a major role in motivating behaviour change to improve population health."
In response to the study, a spokesperson for DNA testing company 23andMe, said: "This systematic review had narrow review criteria and from 10,515 relevant abstracts only 18 studies were included.
"Furthermore, this paper notes that the studies included in the review were predominantly at high or unclear risk of bias, and evidence was typically of low quality."
They added: "Direct-to-consumer genetic testing has been studied in more depth by Robert Green from Harvard Medical School.
"He concluded that when armed with their genetic data, 42% of people reported positive changes in their health behaviour, 72% of people made positive changes to their diet, while 61% made positive changes to their exercise habits.
"Furthermore, data from UK 23andMe customers showed that most (more than 70%) indicated the information they learned from their health and trait reports was 'extremely valuable'.
"It's important to note the way in which testing results are presented is a critical factor in gauging response. We've honed our approach to presenting information over nine years to effectively communicate genetic testing results in a way consumers can understand."
