In the last 2-3 years, several large genetic studies have reported the identification of many
new genes involved in determining risk of Heart Disease. To date, common “variants” in over
20 Heart Disease Risk genes have been identified and their effect on risk confirmed using a
statistically robust “meta-analysis” approach, often in combined samples of more than 20,000
patients, giving good confidence to their impact on risk. Interestingly, while some of these
variants are having their effect on risk by influencing the levels of classical CHD risk factor
traits such as lipids of blood pressure, for most of these genes the mechanism of risk is not
yet understood.
The key fact is that, individually, all of these risk effects are relatively modest, increasing risk
in an individual by 20%-40%, but in combination, their additive effects are high and clinically
important, and may reach 2 fold or greater. To put this into context, this is as large an effect as
being a current smoker. The Genetic Profile Test therefore combines information from these
more than 20 variants to give an overall risk score. This is only of value in the context of
knowing an individual’s other heart disease risk factors such as age, gender, blood pressure,
weight, and lipid levels.
These well-known risk factors are used to estimate the individuals risk by putting the values
into a risk calculator, often called the “Framingham algorithm“, and this is then added with the
genetic risk to obtain an overall score. This information is then used by the consultant
physician, in discussion with the subject, to decide on how best to manage future risk. This
may be by life style changes such as weight loss and smoking cessation, or by offering drug
therapy such as lipid- or blood pressure lowering medication, or most often a combination of
all approaches.
Background
© StoreGene, 2011