Tests Detect Major Common Genetic Risk Factors for Heart Attack and Stroke
Orlando, Florida, November 4-7, 2007 – At this year’s Scientific Sessions of the American Heart Association, deCODE genetics (Nasdaq:DCGN) is presenting its newly launched DNA-based risk diagnostic tests deCODE MI™ and deCODEAF™ -which measure common genetic variants associated with clinically relevant increases in risk of heart attack and atrial fibrillation/stroke, respectively. deCODE has pioneered the discovery of common, single-letter variations in the genome, known as SNPs 1,2, with significant impact on risk of common diseases.
Heart attack and atrial fibrillation/stroke are two of the leading causes of death and morbidity in the industrialized world. deCODE’s tests for genetic risk factors may help identify those at increased risk for these diseases, providing novel and valuable information for physicians in the management of their patients.
To learn more, visit deCODE in the exhibition hall at exhibit 1917 or on the web at www.decodediagnostics.com
The deCODE MI™ test detects two SNPs located on chromosome 9p21, discovered by deCODE and which various genome-wide association studies have confirmed as the highest impact genetic risk factor for heart attack and coronary artery disease identified to date. This discovery was first published in the journal Science earlier this year based on a deCODE study of over 17,000 individuals, and replications of this finding have been published by independent groups in authoritative peer-reviewed journals. More than 20% of the general population have been shown to be positive for the variants in the deCODE MI™ test, and these individuals have roughly double the likelihood of early onset heart attack – that is, prior to the age of 50 in men and 60 in women – compared to those without the risk variants. This genetic risk factor is independent of other risk factors, such as cholesterol, obesity and smoking, and therefore provides an additional method for identifying individuals who may derive benefit from earlier and more aggressive prevention efforts.
The deCODE AF™ test identifies two SNPs discovered by deCODE on chromosome 4, which are associated with a predisposition to atrial fibrillation (AF), the most common cardiac arrhythmia and the leading cause of cardiogenic stroke. As reported in the journal Nature in July 2007, these two SNPs confer approximately 70% and 40% increased risk of AF, respectively. deCODE AF™ measures both of these markers, and approximately 25% of the general population is positive for the test, corresponding to a 1.8-fold increase in risk of AF compared to the rest of the population. deCODE’s test has multiple potential applications. In patients with stroke or transient ischemic attack (TIA) of unknown etiology, which accounts for one-third of these patients, the deCODE AF™ test may determine which patients are at greater risk of AF and therefore may most likely benefit from extended cardiac monitoring for AF. Further, the deCODE AF™ test could be used to screen individuals who have no had a stroke or TIA but in whom AF is suspected. Confirmation with extended cardiac monitoring, impractical and too costly to apply to all patients, may then allow physicians to identify the best therapy for each individual patient.
Visitors to deCODE’s booth also can learn about deCODE T2™, the first genetic risk test for type 2 diabetes, which detects a SNP on chromosome 10. This variant, identified by deCODE last year, has been confirmed in over 40 independent populations and has been shown to be the variant with strongest association to diabetes risk in five genome-wide association studies around the world. In prediabetic individuals, this gene variant is associated with an almost doubling of the average risk of progressing within 3 years to full-blown diabetes, itself a leading risk factor for cardiovascular disease. The presence of two copies of the SNP within an individual’s genome corresponds to an approximate doubling of the risk of developing type 2 diabetes 3,4. Published studies by independent researchers have demonstrated that the variant tested by deCODE T2™ is also indicative of responsiveness to certain drugs. In these studies, the variant is associated with a poor response to treatment with sulfony lureas, while metformin was shown to be effective both for the treatment of diabetes and for reducing conversion rate from prediabetes to diabetes 5,6.
deCODE genetics (Nasdaq:DCGN) is a global leader in applying human genetics to develop drugs and diagnostics 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, and on our diagnostics site at www.decodediagnostics.com.
Physicians and healthcare professionals Media
Clyde Shores Berglind R. Olafsdottir
deCODE diagnostics deCODE genetics
1. Gudbjartsson et al. Variants conferring risk of atrial fibrillation on chromosome 4q25. Nature 2007 Jul 19;448(7151):353-7. Epub 2007 Jul 1.
2. Helgadottir et al. A Common variant on chromosome 9p21 affects the risk of myocardial infarction. Science 2007 Jun 8;316(5830)1491-3. Epub 2007 May 3.
3. Grant SF, Thorleifsson G, Reynisdottir I, et al. Variant of transcription factor 7-like 2 (TCF7L2) gene confers risk of type 2 diabetes. Nature Genetics. 2006;38(3):320-323.
4. Florez JC, Jablonski KA, Bayley N, et al. TCF7L2 polymorphisms and progression to diabetes in the diabetes prevention program. N Engl J Med. 2006;355(3):241-250.
5.Pearson ER, Donnelly LA, Kimber C, et al. Variation in TCF7L2 influences therapeutic response to sulfonylureas: a GoDARTs study. Diabetes. 2007;56(8):2178-2182.