(Image:Jonathan Nackstrand/AFP/Getty)

The Nobel prize in chemistry has gone to research showing how DNA fixes the damage that can cause cancer and premature ageing.

Tomas Lindahl of the Francis Crick Institute in Hertfordshire, UK, Paul Modrich of Duke University in Durham, North Carolina, and Aziz Sancar of the University of North Carolina, Chapel Hill, shared the prize for each finding different ways our DNA is repaired.


Lindahl discovered how DNA gets repaired when a building block, or base, called uracil is loaded into the DNA double helix instead of the correct building block, cytosine. Lindahl found that this happens 200 times a day in every cell of the body, so millions of repairs are necessary daily. On receiving the news that he’d won the prize for the process, called base excision repair, Lindahl said: “I know I’ve been considered before, but it was still a surprise. I feel very lucky and proud to be selected.”

Modrich, meanwhile, discovered how DNA gets repaired if it gets miscopied when cells replicate themselves by dividing to form two daughter cells. As a cell divides, each of the two original strands of DNA gets copied to form one of the strands for a daughter cell, but sometimes, the DNA isn’t copied correctly. Modrich discovered how cells repair this problem through a process called mismatch repair.

Sancar discovered how DNA is damaged by sunlight and mutation-causing agents such as cigarette smoke, and how cells rectify the damage through a process called nucleotide excision repair.

“Together our three Nobel laureates have explained the basic mechanisms that help to guard the integrity of our genomes,” said Claes Gustafsson, chairman of the Nobel Chemistry Committee.

DNA (or its sister molecule RNA) has now won Nobel prizes at least eight times:

1962 This was the big one, the discovery of the structure of DNA, awarded to Francis Crick, James Watson and Maurice Wilkins

1980 For recombinant DNA

1989 This was for showing how RNA catalyses reactions

2001 For the mechanics of cell division

2002 For the discovery of programmed cell death

2006 RNAi interference

2009 How ribosomes make proteins

2015 Mechanism of DNA repair

Read more on the 2015 Nobels:The 2015 Nobel prize for physiology or medicine was awarded to scientists who developed new drugs for roundworm parasites and malaria.

The physics Nobel went to scientists who discovered neutrinos have mass and can change “flavour”.