Professor Douglas Easton said there was a "big excitement" about discovering around 80 genetic variants linked to common cancers.
"We can use this information to develop risk profiles of individuals to identify people who are at either high or low risk of these cancers," he added.
People at high risk would be encouraged to have earlier and more regular screenings for the disease, he said.
More top news
More than a third of children in England are considered overweight, a new 20-year study suggests.
The Tory party's "anti-immigration rhetoric" could cost MPs key marginal seats in the forthcoming general election, a new report says.
Two pilots have broken the world distance record for a flight in a helium balloon after soaring over the Pacific Ocean.