The health secretary is calling for predictive genetic tests for common cancers and heart disease to be rolled out on the NHS without delay.

Matt Hancock, speaking at the Royal Society on Wednesday, revealed he recently took a commercial genetic test that showed he was at heightened risk of developing prostate cancer, saying he was shocked by the result. Hancock called for a national debate about the ethical issues around testing for diseases, some of which could not readily be treated.

He said: “We must get predictive testing into the NHS as soon as we possibly can. I see it as a game-changer for cancer screening in the NHS and I’m determined that we harness this technology to save lives.”

However, the prospect of a rapid rollout of genetic testing has attracted criticism. The tests, which have been largely developed using genetic data from white Europeans, give less accurate results for people from different ethnic backgrounds. Using them to guide health interventions could entrench health inequalities within screening programmes.

Prof David Curtis, a geneticist and psychiatrist at University College London, who has previously raised concerns about racial bias in genetics, said: “You simply can’t have an NHS test that only works for white people. How can you contemplate this?”

Others have raised concerns that genetic tests could create unnecessary stress or confusion or lead to “genetic fatalism”, where people abandon efforts to maintain a healthy lifestyle on the belief they are genetically destined to get a particular illness.

Hancock, 40, recently took a commercial test looking at his genetic risk of 16 diseases. He was at below average risk for most conditions but said: “My risk of prostate cancer by age 75 is almost 15%.” The average lifetime risk is about 12%.

“I was surprised, and concerned,” he said. “But I discussed what it meant with the doctor and when I realised that dying from prostate cancer is highly preventable, if caught at an early stage and with regular checks, I felt hugely relieved. The truth is this test may have saved my life.”

As a result, Hancock said, he has booked an appointment with his NHS GP to discuss the correct course of action. However, Curtis said the health secretary had “massively misinterpreted” his score, which he said revealed he had a fairly average risk of prostate cancer.

“As a result of his misunderstanding, he first suffered unnecessary anxiety and then took up valuable medical time having to be counselled about the reality of the situation. Now he is going to waste even more of the NHS’s scarce resources by booking a completely unnecessary appointment with his GP to discuss a course of action to address a problem which essentially does not exist,” he said. “As a health secretary, he displays a quite astonishing level of ignorance about the NHS.”

Curtis said the value of genetic testing for common diseases had been overstated, since only people at the extremes of the distribution would have significantly higher or lower risk than average.

The company that carried out Hancock’s test, Genomics Plc, has developed similar genetic risk tests for a range of other common conditions including coronary heart disease, breast cancer, asthma and diabetes.

Prof Peter Donnelly, the company’s founder and CEO, said: “I think this is the area where genetics will have its biggest impact on healthcare because it’s all of the common diseases.”

He said that screening programmes for diseases such as breast cancer could be guided by genetic risk, meaning that those at greatest risk would enter screening at a younger age. “A [high risk] women in her early 40s has the same risk as a typical woman in her 60s or a [low risk] woman well into her 70s,” he said. “The world we’re in where we screen women just based on age and offer mammography at 50 just doesn’t make sense.”

He said there remained critical questions about the extent to which people from minority ethnic backgrounds were disadvantaged when it came to test results. Early tests suggested the company’s tests provided information about risk for ethnic minorities, but with less precision.

Donnelly said: “One has to even think really hard about whether it should be rolled out now when it’s more useful for some individuals than others, or if we should wait until we’ve got better data and better methods that help people from different ancestries.”

Hancock has also urged researchers to share more genetic information, saying: “Data, funded by the British taxpayer, donated by the public, can’t be used for predictive testing because of bureaucratic blocking or a scientist wanting to have a monopoly: that’s an outrage. We will unlock that data because we must save lives.”