A population-based study by a team of deCODE scientists
and colleagues at Iceland’s National University Hospital published today
provides a detailed look at the impact of a gene variant on risk of breast
cancer. The variant is within a gene called BARD1 (BRCA1-associated RING
domain 1) and in the study of a total of some 2000 patients and controls
it was found in 5.4% of breast cancer patients and 3.1% of controls, corresponding
to an 80% increase in risk for carriers of the variant in the general population.
Studies in Italy and Finland of specific families with a high incidence
of breast cancer have suggested that variants in the BARD1 gene might play
a role in the disease. Utilizing population-based genealogical and phenotypic
data, the deCODE team was able to demonstrate that the variant confers increased
risk for breast cancer in the population at large. Perhaps the most striking
result is that carrying the variant increases the already high risk of breast
cancer in women who also carry the Icelandic founder risk mutation in the
BRCA2 gene. As the increase in risk is multiplicative, the authors note that
the likelihood of developing breast cancer for women who carry at-risk variants
of both genes may approach certainty. Carriers of the BARD1 variant, with
or without the BRCA2 mutation, also had an increased risk of subsequent primary
breast tumors after the first breast cancer diagnosis.
Testing for the variant may therefore be of clinical utility for identifying
those women who are at an increased risk of breast cancer but who do not
have a clear family history of the disease; those who are carriers of BRCA2
risk mutations and may be at a dramatically higher risk if they also carry
the BARD1 variant; and for evaluating the likelihood that women who have
already been diagnosed with breast cancer will develop a second breast cancer.
deCODE, under its diagnostic partnership with Illumina, aims to use analyses
of these findings in other populations as the basis for developing such a
diagnostic test.
The study, “The BARD1 Cys557Ser variant and breast cancer risk in Iceland,”
is published in the online edition of PLoS Medicine, and is freely available
online at www.plosmedicine.org.
About Breast Cancer
Breast cancer is the second most common cancer and the second leading cause
of death of cancer among women. An estimated 215,000 cases are diagnosed
in the US every year and over 40,000 deaths will result from breast cancer.
Though a substantial portion of risk of this common disease is clearly
familial, it has proven difficult to find genetic variants predisposing
to its common forms. The strongly predisposing mutations in the BRCA1 and
BRCA2 genes have a less than 0.5% frequency in the general population in
the US and Europe. These mutations are estimated to account for only 1-3
% of all breast cancer cases and about 15-25% of the familial component
of breast cancer. There is evidence that a substantial portion of the uncharacterized
risk for breast cancer is genetic, and this has encouraged the search for
additional breast cancer predisposition genes.
About deCODE
deCODE genetics (NASDAQ:DCGN) is a global leader in applying human genetics
to develop drugs for common diseases. Our population approach has enabled
us to discover and target key biological pathways involved in conditions
ranging from heart attack to cancer. We are turning these discoveries into
new medicine to better treat and prevent many of the biggest challenges
to public health. deCODE is delivering on the promise of the new genetics.SM
Visit us on the web at www.decode.com.
Any statements contained in this presentation that relate to future plans,
events or performance are forward-looking statements within the meaning of
the Private Securities Litigation Reform Act of 1995. These forward-looking
statements are subject to a number of risks and uncertainties that could
cause actual results to differ materially from those described in the forward-looking
statements. These risks and uncertainties include, among others, those relating
to technology and product development, integration of acquired businesses,
market acceptance, government regulation and regulatory approval processes,
intellectual property rights and litigation, dependence on collaborative
relationships, ability to obtain financing, competitive products, industry
trends and other risks identified in deCODE’s filings with the Securities
and Exchange Commission. deCODE undertakes no obligation to update or alter
these forward-looking statements as a result of new information, future events
or otherwise.
