Scientists at Dundee University believe they may be a step closer to finding out why some people contract cancer.
Cancer specialists in Dundee will continue their studies into the gene
Researchers have found that people who carry a variant of a specific gene are less likely to develop lung cancer.
The study also revealed that the variant gene can act faster and more effectively to break down a potentially cancer-causing protein.
The team behind the research is now working to see if the discovery has implications for other forms of cancer.
According to the study all humans have the unaltered gene, CYP1B1, while fewer than 10% of people carry its variant.
Dr Thomas Friedberg, who has led the work at Dundee's Ninewells hospital, said the dangerous protein was broken down three times as fast in people with the altered gene.
Having lower levels of the protein corresponds to a lower risk of developing cancer, he said, although the precise relationship is not yet known.
Dr Friedberg said: "We found that the levels of this protein in cells differed depending on the type of the CYP1B1 gene.
"This was because some varieties of the CYP1B1 protein were broken down much faster by cellular enzymes.
"This in turn results in individuals in the metabolism of cancer-causing substances, leading to differences in cancer susceptibility."
He added: "We believe our findings will lead to novel approaches in cancer treatment."
In the past women who carry the changed form of the gene have been found to have lower incidence of the disease compared to individuals with the other forms of the CYP1B1, but the reason was not known.
Dr Friedberg's laboratory research was carried out over three years and funded by the Association for International Cancer Research (AICR).