The genetics of coronary artery disease

Prevention of coronary artery disease (CAD) is an appropriate goal for the 21st century. Randomized clinical studies consistently show a 30-40% reduction in mortality and morbidity by modifying known risk factors. However, genetic risk, estimated to account for 40-60% of susceptibility to CAD, has until recently been unknown. Comprehensive prevention will require knowledge of both.

The 21st century technology has responded to the challenge. Whereas the first genetic risk variant was not discovered until 2007 (9p21), a total of 36 genetic risk factors for CAD have been discovered and verified in large sample sizes. A startling discovery was that over two-thirds of these factors do not act through known risk factors or mechanisms. This obviously has great implications for the pathogenesis of CAD and presents many potential targets for new therapy. These genetic risk factors occur more commonly in the population than expected, with over half of them occurring in more than 50% of the population, and 10 of them occurring in at least 75% of the population.

The role of genetic risk factors in genetic screening for prevention of heart disease is yet to be defined. The technology is already available, but functional analysis may be a prerequisite for their clinical application.