Scottish researchers identified a new genetic location associated with increased risk for colorectal cancer and confirmed two other previously identified locations.

The researchers started by examining more than half a million locations on the genome in about 1,000 Scottish people with early-onset colorectal cancer, as well as 1,000 people without the disease. They theorized that people who got the cancer at a young age would have more genetic variants associated with the disease, making it easier to find those variants. Next, they took the top 15,000 genetic locations identified in phase one and genotyped 2,000 more Scots with colon cancer and 2,000 without. Finally, they took the top five locations from the first two phases and genotyped them in about 27,000 people of various nationalities, half with colon cancer and half without.

From this process, they determined that variants at three locations were associated with increased risk of colorectal cancer, two of which had already been identified in other studies. They mapped them in more detail in an unsuccessful effort to see what nearby genes might be causing the higher cancer rates. Interestingly, the new location they found, on chromosome 11, was associated with colorectal cancer in multiple European populations but only with rectal cancer in the single Japanese group studied (this result awaits further replication).

More: To read an abstract of this paper on the medical database PubMed, click here.