The cause of lupus is unknown. However, researchers believe that various environmental factors can trigger the disease in certain people who are predisposed to it. As with many diseases, genetics are an important piece of the puzzle. There is no single gene that makes people more likely to develop lupus. However, studies suggest that a number of different genes may increase a person’s likelihood of developing it, in addition to determining which tissues and organs are affected and the severity of disease. The Epstein-Barr virus (EBV), which causes mononucleosis, has been identified as a cause of lupus in people whose genes make them more likely to develop it. But genes alone don’t determine who gets the disease.
Researchers are exploring other contributing factors such as exposure to sunlight, stress, hormones, smoking and certain medications. Because lupus often strikes women during their childbearing years, scientists believe that hormones play an important role.
Studies show that regular or long-term exposure to certain insecticides may increase the risk of developing autoimmune diseases such as lupus.