Researchers found gene variants that increase the risk for colorectal cancer

According to a study presented at the American Society of Human Genetics annual meeting, researchers discovered a common genetic variant that increases the risk of colorectal cancer caused by the consumption of processed meat and red meat. “We’re showing the biological underpinnings of these correlations, and understand whether genetic variation may make some people more or less susceptible to certain carcinogens in food, which may have future important implications for prevention and population health,” researchers said.

Colorectal cancer is the third leading cause of death; the causes of colorectal cancer are multiple as the factors that are involved are both genetic and environmental. The study is the first of its kind to highlight the interactions between genes and diet on the genome. Lead author Jane Figueiredo, Ph.D., Assistant Professor of Preventive Medicine at the Keck School of Medicine of USC, said that this study is the first to show whether certain individuals are predisposed to or have a lower risk of colorectal cancer based on their genomic profile. According to Figueiredo, this study helps us to better understand the biology of colorectal cancer and to discover  preventive therapies in the future.

However, the researchers noted that the absence of genetic profile should not encourage people to eat all the red meat they would like. However, Figueiredo explained that the presence of genetic variant allele makes the risk of colorectal cancer to increase even more if people consume high amounts of processed meat.

Over time there have been many studies that have shown that diet has an important impact on health including cancer risk. But the way personal genetic variations alter the effects of diet on cancer risk have not been well analyzed. To study the interactions between genes and the consumption of red meat and processed meat,  researchers analyzed more than 2.7 million genetic sequences.  9287 patients with colorectal cancer and a group of 9,117 individuals without colorectal cancer were included in the study.  A higher risk of colorectal cancer associated with red meat was found in patients with genetic variant rs4143094.

It seems that consumption of red meat and processed meat leads to immunological and inflammatory response that causes cancer development. Normally, a transcription factor called GATA3 helps suppress this response, but when there is a genetic variant in the GATA3 gene region, this immune response is no longer blocked. There are genetic variants that may be beneficial such as variant rs1269486 on chromosome 8. Researchers found that people with this variant that consume fruits and vegetables have a lower risk of colorectal cancer.