Fat Gene Linked to Colon Cancer
Gene for Fat Hormone Affects Colon Cancer Risk
Sept. 30, 2008 -- A fat hormone gene is linked to colon
cancer, researchers find.
The finding provides part of the answer to a big question: What triggers
To get at this question, Boris Pasche, MD, PhD, and colleagues followed a
trail of clues that implicates adiponectin, a hormone made only by fat
- Colon cancer cells have more adiponectin receptors than do normal gut
- People with the highest adiponectin levels have a 47% lower risk of colon
cancer than do people with the lowest adiponectin levels.
Obese people have decreased adiponectin levels.
- Obese people have an increased risk of colon cancer.
The researchers looked at five common variants of the adiponectin gene and
five common variants of the gene for the adiponectin receptor.
They first analyzed adiponectin genes from about 1,100 people of Ashkenazi
Jewish ancestry, including 441 colon cancer patients. This population is at
particularly high risk of colon cancer. Three adiponectin gene variants, and
one adiponectin receptor gene variant, affected colon cancer risk.
The researchers then analyzed the same gene variants in 199 colon cancer
patients and 199 matched controls in mixed-ethnicity Chicago-area residents.
Only one variant of the adiponectin gene was linked to colon cancer, but it was
the same as one of the variants in the first study and reduced the risk of
colon cancer by the same amount.
When the studies were combined, the gene variant cut colon cancer by
"Now, for the first time, we see a gene in these fat cells is linked to
colon cancer," Pasche says.
Evadnie Rampersaud, PhD, research assistant professor at the University of
Miami's Institute for Human Genomics, says it's an important finding.
Rampersaud was not involved in the Pasche study.
"What is unique is this is the first time anybody has identified a
genetic variation, a location within the adiponectin gene, that they can link
to colon cancer," Rampersaud tells WebMD. "That is pretty
What excites Pasche and Rampersaud isn't the specific gene variant linked to
colon cancer. What's much more interesting is that this variant points to a
specific region of the adiponectin gene that affects colon cancer -- and, very
likely, other types of cancer as well.
"This opens the door for more research," Pasche says.
Pasche and colleagues report their findings in the Oct. 1 issue of The
Journal of the American Medical Association.