Blood test for cancer

    A new blood test for cancer will look for the signs of the disease by identifying white blood cells that have already sustained damage from fighting the cancer cells.
    The test will be based on theory that the stress caused to the white blood cells could be measured under the right circumstances. By exposing DNA to UV light and then prompting the DNA to move through an agar medium, it will be possible to determine the amount of damage the DNA has sustained by observing the length of its comet-like tail. A longer tail will indicate a looser DNA structure - which is a sign of damaged DNA. And since the DNA of people battling cancer cells is more easily damaged by UV light than healthy DNA, the test has the potential to be a useful diagnostic tool.