Heart disease is an umbrella term referring to a number of diseases affecting the heart; it does not refer to just one single condition. Sometimes people also use the term cardiovascular disease to refer to the same thing. Being a prevalent cause of death in many developed countries including the USA, heart disease is a major health concern. The disease obviously affects the heart or rather, the cardiovascular system including arteries, capillaries and veins. Heart conditions which would be classified under the term “heart disease” include:
- Heart infections: infection of the heart chambers caused by viruses, bacteria or funguses.
- Congenital heart defects – these are conditions a child would be born with and are often genetic
- Arrhythmias – problem with irregular heart beat
- Disease of the blood vessels (such as the aforementioned coronary heart disease)
What are the causes of heart disease?
Different heart diseases have different causes. Certain conditions can, for example, lead to arrhythmias such as congenital heart defects, high blood pressure or smoking.
Heart infections are causes by viruses, bacteria or parasites. These organisms would usually enter the blood stream first and then infect the heart. Some viruses responsible for sexually transmitted diseases can also infect the heart.
The heart also gets “diseased” through a buildup of plaque – a condition which is known as Atherosclerosis. Coronary heart disease is typically a result of cholesterol and fatty deposits in the arteries and is usually caused by unhealthy eating habits (although there is also a strong genetic component and some people may be genetically predisposed placing them more at risk). Being overweight or obese, smoking and having diabetes may also be risk factors with a considerable impact on risk.
Genes versus Lifestyle
We can of course, exclude heart infections as having a genetic link. Any heart disease caused via bacterial, viral or parasite infection we have little or no control over and whether we contract such a disease or not is entirely unrelated to our genetic makeup. Heart infections would thus, have no genetic links. This said, some people may be more susceptible to them due to a weakened immune system which could itself be the result of a genetic condition. Their weakened immune system would obviously make them more susceptible to infection.
In most cases, coronary heart disease is a disease of old age. People who lead healthy lives in their younger years are less likely to develop the condition. Many people over the age of 50 suffer from this condition and although people with an unhealthier lifestyle are more likely to develop it, there are many cases of people who lead healthy, smoke free and alcohol free lifestyles and who still develop the disease. This has prompted scientists to investigate whether there are any genetic links.
Heart disease tends to run in families and people with blood relatives who have been afflicted by heart diseases are more likely to suffer from heart disease themselves. But a healthy lifestyle can help alter your genetic destiny and keep the disease at bay.
One of the main genes involved is the FLAP gene (5-lipoxygenase activating protein) and people with this particular gene double their chance of developing some types of cardiovascular diseases (such as, coronary heart disease). The gene causes inflammation by triggering the synthesis of leukotrienes (inflammatory chemicals). Genetic predisposition testing for coronary heart disease is possible. This is a simple DNA test that will estimate your chances of developing this disease. To have the DNA test done, all you need to provide is a DNA sample which can be collected by an oral swab. As mentioned, leading a healthier lifestyle might help avoid developing the disease. The genetic predisposition DNA test is useful especially if you have a family history of heart disease. It could help you know just how elevated your risk of developing the condition actually is.
Although the FLAP gene seems to be one culprit, there are other genes which are also being studied. One study carried out by the University of Utah found that certain genetic variations contribute towards a receptor for low density lips (LDL cholesterol) or what we can classify as bad cholesterol.
Simon Meadows is an online free lance writer currently reading a Masters in Science at University. In his spare time, Simon writes articles about genetic analysis and DNA tests, a field of particular interest to the author. Those wishing to read more articles by the Author can find a broad list by visiting www.easydna.co.nz.