“Scientists and doctors developed the spit test after studying the DNA of hundreds of thousands of men. It works by looking for genetic signals in the saliva that are linked to prostate cancer.

In the Barcode 1 trial, researchers recruited more than 6,000 European men to trial the spit test. All were recruited from their GP surgeries and were aged between 55 and 69 – an age at which the risk of prostate cancer is increased.

Once the saliva had been collected, the test calculated the polygenic risk score (PRS) of each of the men. The score is based on 130 genetic variations in DNA code that are linked to prostate cancer.

In those with the highest genetic risk, the test returned fewer false positives than the PSA test, picked up people with cancer who would have been missed by the PSA test alone, and picked up a higher proportion of the aggressive cancers than the PSA test, the ICR said.

The test also accurately identified men with prostate cancer that had been missed by an MRI scan.”

From The Guardian.