deCODE is applying its breakthrough discoveries
in the genetics of common diseases to develop DNA-based diagnostic
tests. Such tests offer a novel means of gauging individual susceptibility
to disease, and may enable better-informed and more effective
prevention and treatment strategies.
deCODE is a global leader in the discovery of genetic variants
that confer increased risk of common diseases. Common diseases
occur at the interface of genes and the environment, as both
inherited as well as lifestyle and environmental risk factors
play important roles in the disease process. Carrying a genetic
risk variant for a common disease does not mean that one will
necessarily develop the disease; and not having a certain risk
variant does not eliminate all risk of developing the disease.
Rather, in the common diseases, genetic risk variants impact
the likelihood that one may develop a given condition. Understanding
this inherited risk is empowering information with potentially
important clinical utility, as it is possible to take preventive
action – through lifestyle modification or by taking certain
medications – to minimize the likelihood of an inherited predisposition
ever developing into a disease. This is similar to the approach
that is taken to address other risk factors for common diseases,
such as high cholesterol, which is commonly treated using statin
drugs to lower the risk of heart disease.
Reference Laboratory Diagnostic Testing
deCODE is developing DNA-based diagnostics to enable individuals,
working with their doctors, to better understand and address
their risk of common diseases. The company has a Clinical Laboratory
Improvement Amendments (CLIA) registered reference laboratory
and began offering DNA testing services in April 2007.
deCODE T2™ for Type 2 Diabetes
In April 2007 deCODE launched deCODE T2™, a novel DNA-based
reference laboratory test for the first common and well-validated
genetic risk factor for type 2 diabetes (T2D). We believe this
test may provide an important means to better gauge individual
risk of T2D and help to guide prevention and treatment strategies.
The sequence variant detected by deCODE T2™ is a single
SNP (a one letter variation in the sequence of the genome)
in the TCF7L2 gene on chromosome 10. In deCODE’s original
findings published in 2006, and in published replications
by independent researchers in numerous populations an ethnic
groups from around the world, between 8-11% of the general
population have been shown to carry two copies of the risk
variant, but roughly twice that number of type 2 diabetics.
In other words, having two copies of the risk variant - a
positive result for the deCODE T2™ test – has been shown
to correspond to an approximate doubling of the likelihood
of T2D.
Additional support for the clinical utility of this discovery
comes from analysis of data from a U.S. government-sponsored
clinical trial – the Diabetes Prevention Program - which
prospectively studied prediabetics (that is, individuals
with blood glucose levels that are intermediate between normal
and Type 2 diabetes) and their progression to Type 2 diabetes.
About a third of prediabetics in this study progressed to
Type 2 diabetes within 3 years. However, among prediabetics
who carried two copies of the gene variant in the deCODE
diabetes test, the risk was substantially greater – 1.8 fold
compared to those who were negative for the test. Weight
loss and drug treatment with either metformin or glitazone
drugs have been shown to reduce progression rates of prediabetics
to T2D. Therefore, this genetic test may be clinically useful
as a means to help physicians to decide which prediabetics
they wish to treat more aggressively either through lifestyle
change or through drug treatment. The U.S. Centers for Disease
Control estimates that more than 50 million American adults
are prediabetic, with either impaired fasting glucose or
impaired glucose tolerance.
For more information on deCODE T2™ and how to order it, visit
our diagnostics website at www.decodediagnostics.com. This
test is also offered via our consumer marketing partner,
DNA Direct, at www.dnadirect.com.
deCODE AF™ for Atrial Fibrillation and Stroke
deCODE AF™ detects versions of two common single-letter variations in the genome (also known as SNPs) on chromosome 4q25 that deCODE has identified as major risk factors for atrial fibrillation (AF). AF is the most common type of cardiac arrhythmia, or irregular heart rhythm, and is the leading cause of cardiogenic stroke. Between 15 and 20 percent of all strokes are cardiogenic, the subtype with the highest morbidity and mortality.
By providing a better understanding of an individual's risk, deCODE AF™ may provide a targeted and cost-effective means to enable doctors to identify those patients who may benefit from outpatient cardiac monitoring for undiagnosed AF. Published research and best clinical practice suggest that individuals with AF, and with a history of stroke or with other risk factors, can significantly reduce their risk of stroke through treatment with the anticoagulant drug, warfarin.
Some stroke patients have intermittent AF and may no longer be in AF when they arrive at an emergency room. Many of these may not be diagnosed during the standard 24 to 48 hours of inpatient cardiac monitoring. As a result, these patients may be placed on an antiplatelet agent rather than much more effective warfarin treatment for secondary prevention of AF-related stroke. More extensive outpatient cardiac monitoring is not routinely done due to the expense involved. deCODE AF™ offers a novel means of meeting this challenge - of identifying those who may benefit from outpatient cardiac monitoring after leaving the hospital, and thereby detecting a greater proportion of AF cases and pinpointing those who would benefit from long-term anticoagulant therapy.
For more information on deCODE AF™ and how to order it, visit
our diagnostics website at www.decodediagnostics.com.
deCODE MI™ for Myocardial Infarction (MI)
deCODE MI™ is a genetic test for increased risk for myocardial infarction (MI or heart attack), especially MI occurring at an early age, or before the age of 50 for men and 60 for women. It is a reference laboratory test which detects single base changes or SNPs in the CDKN2A/2B gene region on chromosome 9. deCODE genetics has reported, based on studies of thousands of patients, that individuals who are positive for this test have twice the risk of developing early onset MI compared to those without the genetic variants. It is also appears to be a risk factor for MI in general, carrying with it a 1.6 fold risk regardless of age. About 20% of the general population are positive for this test. This has been confirmed in US and other European populations.
Healthy living and targeted treatments of risk contributing conditions such as hypertension, diabetes and elevated blood lipids are the cornerstones of modern prevention of cardiovascular diseases, including coronary artery disease and MI.
deCODE MI™ detects a genetic or an inherited risk of MI that is a new risk factor for MI that appears to add risk on top of previously recognized risks. The test may be positive even in patients of families without history of heart attacks. The knowledge of being a carrier of this specific inherited risk is therefore important in the context of one’s overall risk of coronary artery disease and MI and adds emphasis on the importance of effective preventive regimens, both at the personal level and at the patient-doctor level.
For more information on deCODE MI™ and how to order it, visit
our diagnostics website at www.decodediagnostics.com.
Other tests in development
deCODE is also developing tests for genetic variants the company has linked to risk of prostate cancer, and breast cancer, deep vein thrombosis and glaucoma, among other common diseases.
Diagnostic Kits – Illumina Alliance
deCODE is also working with its partner Illumina Inc, to develop
DNA-based test kits for gene variants in several diseases,
including type 2 diabetes, heart attack and breast cancer,
based on Illumina’s clinical genotyping platform, Veracode.
Further Information
For additional information on deCODE’s DNA tests, please write
to info@decode.com.