A gene variant identified by scientists in California and Arizona nearly doubles the risk of a common type of blood cancer.
Researchers at the University of California, Berkeley (UC Berkeley) and at the Translational Genomics Research Institute (TGen) found that mutations in a gene called C6orf15, or STG, are linked to the risk of developing follicular lymphoma.
This is a cancer of the body's disease-fighting network whose rates have nearly doubled in the past three decades.
In the first genome-wide association study of non-Hodgkin lymphoma, scientists identified a SNP - a single nucleotide polymorphism - that could determine susceptibility to follicular lymphoma.
The SNP, a DNA variant within the more than 3-billion base pairs in the human genome, was identified as rs6457327.
The study was led by Dr. Christine Skibola, Associate Adjunct Professor of Environmental Health Sciences at UC Berkeley's School of Public Health, and by Dr. Kevin M. Brown, an Associate Investigator in the Integrated Cancer Genomics Division of TGen, a Phoenix-based, non-profit biomedical research institute.
"What's exciting about this study is that we found a target in the genome influencing the susceptibility to follicular lymphoma, which helps us discern between three major types of lymphomas," said Skibola.
"That had not been done before on a genome-wide scale. It is our hope that this research may some day be useful in helping develop prevention, early detection and treatment of this disease," Skibola added.
The researchers looked at variations in the gene and found that the presence of the G allele of SNP rs6457327 was actually protective against follicular lymphoma, occurring less frequently among people with the cancer.
In contrast, the presence of the A allele was predictive of an increased risk of developing follicular lymphoma. Brown said individuals who had the A allele were nearly twice as likely to develop follicular lymphoma.
"There's clearly a genetic component to the disease. The hope is to one day be able to take these results, combine them with other tests, and turn them into an individualized assessment of disease risk. This is a starting point," said Dr. Brown.
The genome-wide association study was conducted using DNA from a population-based non-Hodgkin lymphoma case-control study in the San Francisco Bay Area led by UC San Francisco researchers. Follow-up validation studies were done using independent case-control studies from Canada and Germany.
To reduce the potential for complicating factors, the more than 3,000 samples in the UC Berkeley-TGen study were from individuals who were HIV negative.
Dr. Brown said future studies could include HIV-positive individuals, if enough samples were made available.
The study has been published online by the science journal Nature Genetics.