British scientists have discovered, in the largest genetic survey to date, that 64 gene variants may slightly predispose certain individuals to lung cancer.

The discovery was made in the new genome-wide survey carried out by Richard Houlston of the Institute of Cancer Research, in Sutton, and his colleagues, a report on the latest website of the New Scientist said.

These 64 DNA variants are known as "low-penetrance alleles" because they only occasionally stimulate tumor development.

To identify the genes, Houlston's team analyzed the DNA in blood samples collected from 1529 people with lung cancer and from 2707 individuals without the disease. In total, they investigated 871 genes among the volunteers, all of whom were white.

Of the 64 gene variants the researchers found, 11 were located within genes that encode key parts of a biological pathway involving an insulin-like growth factor.

Houlston suggested that scientists developing future treatments for lung cancer may want to consider targeting this pathway. But he stressed that the risk of lung cancer conferred by these genetic changes was minute compared to one particular lifestyle choice: smoking, the biggest risk factor for lung cancer.

Lung cancer claims approximately 1.2 million lives worldwide each year and the discovery was seen as a step towards developing tests to identify those at high risk of developing the deadly condition.

Source: Xinhua