The 2015 Nobel Prize in Chemistry has been awarded for discoveries in DNA repair.
Tomas Lindahl and Paul Modrich and Aziz Sancar were named as the winners on Wednesday morning at a news conference in Stockholm, Sweden.
Their work maps how cells repair damaged DNA - a process that is fundamental for living cells.
The prize money of eight million Swedish kronor is divided among the winners.
"I know I have been considered for prizes in the past, but so have hundreds of others. I feel lucky and proud to be selected today," Tomas Lindahl, from the Francis Crick Institute in the UK, told journalists.
Claes Gustafsson, from the Nobel Committee, said the recipients had "explained the processes at the molecular level that guard the integrity of our genomes".
The Nobel Prize in Physics was awarded on Tuesday to Takaaki Kajita and Arthur McDonald for their work on neutrinos.