Nobel Prize in Chemistry honors DNA research that could lead to new cancer treatments

Three scientists won the world's top science prize today, for their "mechanistic studies of DNA repair." Their work mapped how cells repair deoxyribonucleic acid (DNA) to prevent damaging errors from appearing in genetic information.

Tomas Lindahl, Paul L. Modrich and Aziz Sancar today received the Nobel Prize in Chemistry for "having mapped and explained how the cell repairs its DNA and safeguards its genetic information," the New York Times reports.

"Their work has provided fundamental knowledge of how a living cell functions," read the committee's announcement. The knowledge revealed by the scientists' research could be "used for the development of new cancer treatments."

From the New York Times:

Dr. Lindahl, of the Francis Crick Institute in London, was honored for his discoveries on base excision repair — the cellular mechanism that repairs damaged DNA during the cell cycle. Dr. Modrich, of the Howard Hughes Medical Institute and Duke University School of Medicine, was recognized for showing how cells correct errors that occur when DNA is replicated during cell division. Dr. Sancar, of the University of North Carolina at Chapel Hill, was cited for mapping the mechanism cells use to repair ultraviolet damage to DNA.

"Their systematic work has made a decisive contribution to the understanding of how the living cell functions, as well as providing knowledge about the molecular causes of several hereditary diseases and about mechanisms behind both cancer development and aging," said Nobel Prize organizers at the Royal Swedish Academy of Sciences.


Here's a deeper dive into why these scientists won, and what's in it for you, from the Nobel Prize committee.

Each day our DNA is damaged by UV radiation, free radicals and other carcinogenic substances, but even without such external attacks, a DNA molecule is inherently unstable. Thousands of spontaneous changes to a cell's genome occur on a daily basis. Furthermore, defects can also arise when DNA is copied during cell division, a process that occurs several million times every day in the human body.

The reason our genetic material does not disintegrate into complete chemical chaos is that a host of molecular systems continuously monitor and repair DNA. The Nobel Prize in Chemistry 2015 awards three pioneering scientists who have mapped how several of these repair systems function at a detailed molecular level.

In the early 1970s, scientists believed that DNA was an extremely stable molecule, but Tomas Lindahl demonstrated that DNA decays at a rate that ought to have made the development of life on Earth impossible. This insight led him to discover a molecular machinery, base excision repair, which constantly counteracts the collapse of our DNA.

Aziz Sancar has mapped nucleotide excision repair, the mechanism that cells use to repair UV damage to DNA. People born with defects in this repair system will develop skin cancer if they are exposed to sunlight. The cell also utilises nucleotide excision repair to correct defects caused by mutagenic substances, among other things.

Paul Modrich has demonstrated how the cell corrects errors that occur when DNA is replicated during cell division. This mechanism, mismatch repair, reduces the error frequency during DNA replication by about a thousandfold. Congenital defects in mismatch repair are known, for example, to cause a hereditary variant of colon cancer.

The Royal Swedish Academy of Sciences also published this helpful backgrounder on the research, written in easy to understand terms. [PDF]

Tomas Lindahl poses for photographers after winning the Nobel Prize.  REUTERS/Stefan Wermuth

Tomas Lindahl poses for photographers after winning the Nobel Prize. REUTERS/Stefan Wermuth