Genetic Variation for Heart Attack Risk Found

A variation in a gene that affects inflammation can increase a person’s risk of having a heart attack, Japanese scientists said on Wednesday.

A variation in a gene that affects inflammation can increase a person’s risk of having a heart attack, Japanese scientists said on Wednesday. They found that the genetic alteration is more common in patients who have had a heart attack. It is also linked to a protein called galectin-2 that could be a new drug target to prevent heart attacks. “We have identified…a gene that is associated with susceptibility to myocardial infarction,” Dr Toshihiro Tanaka of the Institute of Physical and Chemical Research (RIKEN) in Tokyo, said in an e-mail interview. Myocardial infarction (MI), or heart attack, is one of the leading causes of death in the world. In the United States alone, about 1.1 million people suffer a heart attack each year and around 460,000 are fatal. It occurs when the blood supply to the heart is stopped and cells in the heart muscle begin to die. Chest discomfort and pain, shortness of breath, a cold sweat and nausea are warning signs. Galectin-2 is a protein that binds to a molecule called lymphtoxin-alpha LTA. Tanaka and his team suspect the genetic variation affects the amount of LTA that is secreted and the degree of inflammation that occurs. “Decreased expression of galectin-2 might be protective against the risk of MI, so drugs that can reduce the function of galectin-2 can be therapeutic,” added Tanaka, who reported his findings in the science journal Nature. Several factors can increase the risk of a heart attack. Anyone who has pre-existing coronary heart disease, angina or a previous heart attack is more likely to suffer another one. Men over 45 years old and women over 55 and people with a family history of heart attacks have a raised risk. Smoking, high blood pressure, raised cholesterol, being overweight or obese, lack of exercise and diabetes are also risk factors. But cholesterol-lowering drugs called statins and treatment to control high blood pressure decrease the odds of having a heart attack. Galectin-2 is not secreted into the blood but Tanaka said levels of the protein can be examined from DNA of white blood cells in blood. He believes the discovery of the genetic variation could lead to other risk factors for heart attack and increase understanding about why it occurs. “We are thinking of the possibility that galectin-2 might play a key role in the inflammation process of myocardial infarction,” he added. (Source: Reuters Health News, May 2004)