News Science Breakthrough Could Finally Help Doctors Pinpoint a Patient's Cancer Cause By Melissa Breyer Editorial Director Hunter College F.I.T., State University of New York Cornell University Melissa Breyer is Treehugger’s editorial director. She is a sustainability expert and author whose work has been published by the New York Times and National Geographic, among others. our editorial process Melissa Breyer Updated April 15, 2019 Public Domain. PublicDomainPictures Share Twitter Pinterest Email News Environment Business & Policy Science Animals Home & Design Current Events Treehugger Voices Scientists find that tumors hold information like a 'black box' pointing to the specific cause of disease. Cancer is a devastating disaster of a disease. As well as a perplexing one ... as in, where does it come from? Sometimes it is genetic, but environmental factors have long played a role in the development of the disease – and finding those causes specifically has been elusive. Until now, that is. According to a statement from the University of Cambridge, scientists have developed "a catalogue of DNA mutation 'fingerprints' that could help doctors pinpoint the environmental culprit responsible for a patient's tumour – including showing some of the fingerprints left in lung tumours by specific chemicals found in tobacco smoke." This is remarkable. We may finally be able to look at a patient's tumor and figure out the exact chemicals that caused the mutations. As Sarah Knapton describes it for The Telegraph, the scientists "have shown that tumours hold information like a 'black box' pointing to the cause of disease." This can only come as bad news for corporations whose products contain carcinogens; corporations that get away with selling potentially deadly products because the causes of cancer have always been so difficult to prove. And for that, this is a win for the general public. The research was done by scientists at the at the University of Cambridge and King’s College London, who have created a catalogue of the mutational 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," explains Dr Serena Nik-Zainal from the Department of Medical Genetics and MRC Cancer Unit at the University of Cambridge, who led the Cambridge Team. "They allow us to treat tumours as a crime scene and, like forensic scientists, allow us to identify the culprit – and their accomplices – responsible for the tumour." Some of the environmental agents the team studied are known carcinogens – like polycyclic hydrocarbons and sunlight. They also looked at some of the specific chemicals found in tobacco smoke and identified which ones cause signatures similar to those found in smokers' lung cancer, explains Cambridge. They also figured out the tell-tale fingerprints left behind by common chemotherapy drugs, some dietary chemicals, and a few found in diesel exhaust fumes. Among so many things, the research reveals how our DNA is vulnerable to so many things around us. In the future, the researchers hope to hope expand the list further to produce an encyclopedia of mutation patterns caused by environmental agents. "Our reference library will allow doctors in future to identify those culprits responsible for causing cancer," says Nik-Zainal. "Such information could be invaluable in helping inform measures to reduce people's exposure to potentially dangerous carcinogens."