Genetic testing for atherosclerosis risk: inevitability or pipe dream?

Family history is a risk factor for coronary artery disease (CAD). However, defining this risk at the DNA level has been elusive. In 2007, four genome-wide association studies reported a strong association between CAD and a region on chromosome 9p21. The high-risk genotype was identified in up to 30% of individuals, creating the potential for a clinical genetic test to assist in the calculation of a patient's CAD risk. However, the reported effect size of the association is modest (OR of approximately 1.3). The present paper examines the feasibility of including DNA tests in CAD risk prediction algorithms. The greatest contribution from the 9p21 association is likely yet to come, as further studies identify the mechanistic basis for the association, possibly leading to additional insights into the progression, prevention and treatment of CAD.