It is difficult to know exactly what causes a person to develop lupus. There are probably multiple factors which predispose someone to develop lupus such as genetics or exposures. If you have a family member with an autoimmune disease you may have a higher risk of lupus, indicating a genetic link. Environmental triggers are thought to include viral infections, exposure to silica dust, sun exposure, various medications and hormones. Estrogen is thought to be an important trigger for the development of lupus. This may be why women develop this condition more readily than men and during reproductive years. Researchers are working to determine more precisely the cause or causes of lupus.