Washington: It is well known that men with relatives who have been diagnosed with prostate cancer have an elevated risk of developing this type of cancer.
In 2010, scientists of the German Cancer Research Center (Deutsches Krebsforschungszentrum, DKFZ) calculated that this risk rises with the number of affected direct family members and also depends on the relatives`` age at outbreak of the disease.
Now, an international research consortium along with DKFZ scientists have discovered seven DNA regions for which an association with an increased prostate cancer risk has now been established for the first time.
The collaborators systematically searched the whole genome of cancer patients and healthy controls for specific gene variants. Then they calculated whether specific variants are found more often in patients than in healthy people.
“Each of these gene variants taken on its own is associated with only a slight increase in prostate cancer risk by a few percent. However, by taking account of the different variants at the same time it becomes possible to identify groups of persons who have a significantly elevated risk,” said Professor Dr. Hermann Brenner, one of the DKFZ researchers.
“ Examining the genetic material for such risk variants might therefore improve medical consultation on the prevention and early detection of prostate cancer in the future,” he added.
Such DNA variants are scientifically called single nucleotide polymorphisms (SNPs). If a relationship in numbers is found between a particular SNP and cancer incidence, researchers conclude that a gene within the affected DNA region plays a role in cancer.
Alongside a number of already identified variants, the investigators found seven SNPs that emerged for the first time in association with an elevation in prostate cancer risk.
The variants are all located in DNA regions that also contain genes for which the scientists consider it plausible that they play a role in carcinogenesis.
However, an association with the malignancy of cancer could not be established for any of these variants.
With the seven newly discovered DNA regions, scientists are now able to explain about 25 percent of familial cancer risk.