Causes of cancer show up in DNA of tumours
The cause of cancer is written into the DNA of tumours, scientists have discovered, in a breakthrough that could finally show how much disease is attributable to factors such as air pollution or pesticides.
Until now the roots of many cancers have proved elusive, with doctors unable to tease out the impact of myriad carcinogenic causes that people encounter every day.
In the case of lung cancer, it is not known how much can be attributed to smoking and how much could be linked to other factors, such as living by a busy road or inhaling pollutants.
Now scientists at Cambridge University and King's College London have exposed stem cells to dozens of known carcinogens and recorded how each alters its DNA code as cancer forms. It provides a "fingerprint" or "mutational signature" of the underlying cause and could even show the biggest culprit.
The researchers have released a catalogue of the signatures caused by 41 environmental agents linked to cancer.
"Mutational signatures are the fingerprints that carcinogens leave behind on our DNA, and just like fingerprints, each one is unique," said Dr Serena Nik-Zainal, from the department of medical genetics at Cambridge. The research was published in the journal 'Cell'.