Toronto, Nov 18 (IANS) Canadian researchers say they have identified four new genes responsible for colorectal or colon cancer.This brings to 10 the total number of genes linked to the disease, which is the second biggest cause of cancer-related deaths in Canada and the western world. More than 650,000 people die of this disease each year in the West.

Over 21,000 Canadians are likely to be diagnosed with colon cancer this year, leading to 8,900 deaths.

In their study, the Canadian researcher team said the presence of the new genes (called genetic markers) could lead to a six-fold increase in the lifetime risk of developing colorectal cancer.

As part of their study with international collaboration, the researchers examined 38,710 genes or genetic markers in 13,315 people from Canada, Britain, Finland and Germany.

“These important findings will help us better understand why some people with a family history develop colorectal cancer and others don’t,” said Heather Chappell of the Canadian Cancer Society.

“Whether you are at high risk for the disease or not, screening continues to be one of the best ways to prevent colorectal cancer,” he said.

“The benefits of this research are immense,” said co-researcher Brent Zanke of the Ottawa Health Research Institute.

“If people know they have an increased risk of developing colorectal cancer, they can make changes to their lifestyle and undergo physical screening tests more often and that may save lives.”

He stressed that people who think they may be at higher risk or have a family history should chalk out an individual screening plan.

Currently, six monthly screenings using the foecal occult blood test (FOBT) are recommended for people above 50.

The study says the discovery of four additional genes linked to colon cancer may lead to the development of an additional screening tool for those people with a strong family history - a genetic test for colon or colorectal cancer risk.

The study has been published in the Nov 16 online issue of Nature Genetics.