Scientists systematically searched 2.7 million variants to identify those that are associated with the consumption of red meat and processed meat as well as fruits and vegetables. The genetic sequences and information about the participants' medical history and diet are in the GECCO database.
A significant interaction between the genetic variant rs4143094 and processed meat consumption was detected. This variant is located on the same chromosome 10 region that includes GATA3, a transcription factor gene previously linked to several forms of cancer. The transcription factor encoded by this gene normally plays a role in the immune system.
On chromosome 8, a statistically significant diet-gene interaction was found in another variant, rs1269486. This variant was associated with reduced risk of colorectal cancer.
How specific foods affect the activities of genes has not been established. Drs. Peters and Figueiredo speculate that digestion of processed meat may promote an immunological or inflammatory response that may trigger tumor development. The GATA3 transcription factor normally would help suppress the immunological or inflammatory response. However, if the GATA3 gene region contains a mutation, it may encode a dysregulated transcription factor that impacts its ability to suppress the response.
In addition to uncovering a novel gene-diet interaction for colorectal cancer, the GECCO study may have important implications for understanding the underlying causes and biological pathways of cancer, said Dr. Peters.
"Our study highlights two genetic regions that are biologically interesting in cancer," she said, referring to the variants located near GATA3 and at 8q23.3.
"These genetic loci may have interesting biological significance given their location in the genome, and further functional analyses are required," said D
|Contact: Cathy Yarbrough|
American Society of Human Genetics