DNA repair scoops Nobel

Stockholm/London, Oct 7

Three scientists from Sweden, the United States and Turkey won the 2015 Nobel Prize for Chemistry on Wednesday for working out how cells repair damaged DNA, providing new ammunition in the war on cancer.

Detailed understanding of DNA damage has helped drive a revolution in cancer treatment as researchers develop new drugs that target specific molecular pathways used by tumour cells to proliferate.

Tomas Lindahl, Paul Modrich and Aziz Sancar won the prize for “mechanistic studies of DNA repair”. Their work mapped how cells repair deoxyribonucleic acid (DNA) to prevent damaging errors from appearing in genetic information.

In many forms of cancer, one of more of these repair systems is broken. “Their work has provided fundamental knowledge of how a living cell functions and is, for instance, used for the development of new cancer treatments,” the Royal Swedish Academy of Sciences said.

Thousands of alterations to a cell’s genome occur every day due to spontaneous changes and damage by radiation, free radicals and carcinogens - yet DNA remains astonishingly intact.

To keep genetic materials from disintegrating, a range of molecular systems monitor and repair DNA, in processes that the three award-winning scientists helped map out. “It’s important for cancer prevention and cancer treatment.

That is what I received it for,” Sancar, who has US and Turkish citizenship and is a professor at the University of North Carolina, told Reuters by telephone from his home.

Sancar said he had been inundated by calls but his immediate plans were to shower, shave and go to his lab.

Modrich, a researcher at the Howard Hughes Medical Institute and Duke University School of Medicine in the United States, told Reuters he received the news while on vacation at his cabin in New Hampshire and was completely taken aback.

In fact, he did not get the word from Stockholm until around 8 am ET, more than two hours after the initial announcement.

Modrich, whose work led to an understanding and diagnostic tests for the most common form of hereditary colon cancer, has previously told how he was inspired by his biology teacher father, who said: “You should learn about this DNA stuff.” That was in 1963, the year after the Nobel Prize was awarded for the discovery of the structure of DNA.

The 8 million Swedish crowns ($969,000) chemistry prize is the third of this year's Nobels. Previous winners of the chemistry prize have included Ernest Rutherford, Marie Curie and Linus Pauling. — Reuters

How cells repair DNA damage 

• When cells divide, molecular machines seek to replicate the code perfectly, but random slipups in their work can cause the daughter cells to die or malfunction. DNA can also be damaged by strong sunlight and other environmental factors
• But there is a swarm of proteins — a molecular repair kit — designed to monitor the process. It proof-reads the code and repairs damage
• The three were lauded for mapping these processes, starting with Lindahl, who identified so-called repair enzymes - the basics in the toolbox

Key to life on Earth

• In the early 1970s, DNA was viewed as a stable molecule but Tomas Lindahl showed it actually decayed at a rate that ought make the development of life on Earth impossible, which in turn led him to uncover the counteracting repair process
• Aziz Sancar, meanwhile, worked out how cells repair ultra-violet damage and Paul Modrich uncovered the mechanism for correcting errors during cell division
• The three opened a dazzling frontier in medicine by unveiling how the body repairs DNA mutations that can cause sickness and contribute to ageing