Heart disease, an umbrella term for a number of diseases that affect the heart, is the leading cause of death in the United States. Heart disease develops when the heart is no longer able to efficiently pump blood throughout the body to oxygenate the tissues, due to weakening or dysfunction of the heart muscle. A number of factors, including several genetic factors, contribute to the risk of developing cardiovascular disease.
MMP3
One gene that may be a marker for heart disease is MMP3. The MMP3 gene codes for the matrix metalloprotease stromelysin protein, which belongs to a class of proteins called matrix metalloproteases. These proteins generally function to cleave existing proteins and can serve a range of functions within the body, including the maintenance and remodeling of the cardiovascular tissue.
A study published in Current Biology in 2004 by Dr. M. Rockman indicates that some forms of MMP3 are associated with a decreased risk of heart disease, with a variant of the gene being implicated in the development of heart disease. Genetic screening to test MMP3 gene variants in patients may act as a predictive genetic marker for heart disease.
APOE
APOE, which codes for the protein apolipoprotein E, is another possible genetic marker for heart disease. Apolipoprotein E combines with lipids within the bloodstream to form very low density lipoproteins, or VLDLs. VLDLs function to regulate the amount of cholesterol in the bloodstream, and dysregulation of blood cholestrol plays a role in the development of heart disease.
The Genetics Home Reference reports that there are three variants of APOE, termed e2, e3 and e4. Patients who carry the e4 variant of APOE are at a higher risk for developing atherosclerosis, which can lead to heart disease. Genetic testing to determine a patient's APOE variants may act as a genetic marker for the development of heart disease and a predisposition to atherosclerosis.
IL-1
IL-1, or interleukin 1, may also act as a genetic marker for heart disease. IL-1 belongs to a class of proteins called cytokines, and it functions to regulate inflammation. When IL-1 is released from tissues, it can recruit cells of the immune system and increase inflammation. Since sustained inflammation has been linked to cardiovascular disease, IL-1 has been identified as potentially involved in the development of heart disease, so it may be a marker for heart disease.
A study performed at Interleukin Genetics by Dr. P. Reilly indicates that some variants of the IL-1 gene are associated with an increased risk for heart disease. Dr. Reilly found that patients carrying a specific variation of IL-1 were almost four times as likely to develop heart disease. This variation to IL-1 may serve as a genetic marker to assess a patient's risk of heart disease.
