The simple saliva test can identify almost half of women who will get breast cancer in the next decade, thus potentially saving the lives of thousands of people under-50. Health and Social Care Secretary Sajid Javid has hailed the research as ‘promising’.

It is viewed as particularly important in identifying women who have a high genetic risk of developing breast cancer but are unable to get a mammogram on the NHS due to their age.

The test has been the subject of a major study which looked at almost 2,500 women’s risk of developing breast cancer. Of these women, 644 developed breast cancer, having been followed up by the researchers after an average of ten years.

The test, which also takes a patient’s health records and breast density into account, accurately predicted a higher risk of breast cancer in just under 50 per cent of those who eventually developed cancer.

Professor Gareth Evans from Manchester University, who led the study, emphasised the value of the test in younger women: “It is particularly important for women under 50, who make up one in five cases of breast cancer”. He stated that the test could save the lives of 2,000 at-risk women a year if they were given preventative drugs following receiving a high-risk score.

Researchers are hoping that the one-off genetic test is provided to women at around the age of 30 and is estimated to cost the NHS around £250. This is a considerable saving long-term as a single breast cancer treatment can cost the NHS thousands of pounds.

Dr Kotryna Temcinaite, of Breast Cancer Now, said: ‘Every year 55,000 women and 370 men are diagnosed with breast cancer in the UK. Early detection can stop people dying from breast cancer, which is why we need research like this to understand how a more tailored approach to breast screening could work.’