Study Identifies Genetic Loci Linked To Colorectal Cancer In East Asians

Researchers have identified three new genetic risk factors linked to colorectal cancer in East Asians.

AsianScientist (Feb. 14, 2013) – Scientists have identified three new genetic risk factors linked to colorectal cancer in East Asians, which may reveal new insights into the biology and potential therapeutic targets of the disease.

Despite being one of the most commonly diagnosed malignancies in East Asia, the genetics of colorectal cancer has not been well established yet. To date, rare genetic variants linked to this malignancy only account for less than six percent of colorectal cancer cases. In addition, genetic risk factors relevant to the Asian populations are not well studied as previous genetic studies have mainly focused on European populations.

Here, researchers from China, Japan, and South Korea established the Asia Colorectal Cancer Consortium (ACCC) that looked at novel genetic risk factors for colorectal cancer. This genome-wide association study, published recently in Nature Genetics, reports some of the findings made by the ACCC researchers.

Using genomic data from 2,098 colorectal cancer samples and 5,749 control samples, the team shortlisted 64 potential variants, or single-nucleotide polymorphisms (SNPs), linked to colorectal cancer.

After replicating their findings in an independent set of samples they narrowed down the list to four, and three of the four variants were found associated with colorectal cancer in a large European population. The investigators noted a weaker association with these variants in the European population, which made them believe that the genetic variants driving the disease might be different for the Asian and European ancestry.

Critical genes linked to cancer are found located close to the four risk variants identified by this study, the authors found. One of them is the gene encoding cyclin D2, CCND2, which is important in regulating the cell cycle machinery. Dysregulation of the cell cycle leads to tumor formation, and cyclins have been frequently linked to cancer. As current studies on CCND2 are few, the study suggested the need for more extensive research on the role of cyclins in the development of colorectal cancer.

“These new discoveries are very exciting,” said Wei Zheng, M.D., Ph.D., MPH, senior author of the study. “They will certainly lead to future studies regarding the biology of these regions and the translational potential of these findings in cancer prevention and treatment.”

The article can be found at: Jia WH et al. (2012) Genome-wide association analyses in east Asians identify new susceptibility loci for colorectal cancer.


Source: Vanderbilt University Medical Center; Photo: source/Flickr/CC.
Disclaimer: This article does not necessarily reflect the views of AsianScientist or its staff.

Yuka graduated with a BSc (Hons) in life sciences from the National University of Singapore (NUS), Singapore, and received her MSc in cancer biology at University College London, UK.

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