Researchers Identify New Genetic Variants Associated With Colorectal Cancer Risk
Posted: Wednesday, March 20, 2019
In a study in the journal Nature Genetics, researchers found 40 new genetic variants linked to a higher risk of colorectal cancer and reportedly the first genetic variant ever discovered to protect against sporadic colorectal cancer. Seven authors led the research, including Li Hsu, PhD, and Tabitha Harrison, MPH, of Fred Hutchinson Cancer Research Center, Seattle.
“With this study, we’ve brought the known number of risk variants for colorectal cancer to nearly 100,” said Ms. Harrison in an institutional press release. “Individuals with genetic risks in the top decile could benefit from earlier screening by colonoscopy,” said Dr. Hsu.
The study included more than 125,000 people: 58,000 patients with colorectal cancer and 67,000 healthy controls. The researchers performed whole-genome sequencing on 1,439 patients and 720 healthy controls. Of the people in the study, 91% were of European descent.
The researchers discovered 40 new variants linked to a higher risk for colorectal cancer and confirmed 55 variants that were already known. Some of these variants are implicated in immune function. The authors also discovered reportedly the first known genetic variant that protects against sporadic colorectal cancer, by far the most common kind of colorectal cancer. This variant is rare: its frequency was 0.3%. The variant is near the chromatin remodeling factor CHD1 gene; the authors hypothesize that it lowers CHD1 expression.
The study is limited by its focus on mostly white patients, however. “Next, we’re broadening the study population to include people from diverse ethnic backgrounds,” said Ms. Harrison. “This will give us a more complete understanding of risk across the entire population.”
Disclosure: The study authors’ disclosure information may be found at nature.com.