Lupus occurs when your immune system attacks healthy tissue and cells within the body. Although there isn’t a clear cause of lupus, many researchers believe that it is caused by a complex interplay of genes, hormones, and environmental factors.
When patients first present signs of lupus, they are often asked whether they have a family member with lupus or another autoimmune condition. This occurs because there is a link between genetics and lupus. It tends to run in families, and there is an increased prevalence of the disease among certain ethnic groups.
Understanding a patient’s genetic background is useful in order to establish a lupus diagnosis because there are a variety of ways that heredity impacts this condition. People with an inherited predisposition for lupus may develop the disease when they come into contact with something in the environment that triggers it. A patient can be born with the specific gene that causes lupus, but that does not necessarily mean they will develop lupus in their lifetime. The severity of symptoms can also vary.



Hormones are also known as the body’s messengers, because they are responsible for the adjustment of many of internal functions. Because lupus primarily affects women and the female body produces greater amounts of estrogen, this may indicate that estrogen regulates the severity of lupus. Many women have more lupus symptoms prior to the start of their menstrual cycle, and symptoms also increase during pregnancy. These are two points at which estrogen production is very high.
However, a direct link between lupus and estrogen, or any other hormone, has not yet been proven. In fact, studies that focus on women whose estrogen levels are impacted by birth control pills or postmenopausal treatment have not shown any increase in lupus activity.



In general, lupus is more likely to be diagnosed in patients with a family member who has already been diagnosed with the condition. However, a specific gene or a group of genes has not yet been proven to be responsible for lupus. Certain genes have been identified as contributing to the development of lupus, but these associations are not significant enough to be considered a direct cause. Lupus can also develop in people with no family history of the condition, but these patients are likely to have a family history of other autoimmune diseases.



Many researchers believe that lupus can be triggered by an environmental agent, such as a virus or chemical, when it is randomly encountered by a genetically susceptible individual. However, this hypothesis remains unproven because no specific environmental agent has been found to be consistently responsible for inducing lupus or causing flare-ups of the condition. The most well-known environmental elements that can have this effect are ultraviolet light (UVB in particular); infections (including the Epstein-Barr virus), and exposure to silica dust in agricultural or industrial settings.
Other examples of known environmental triggers include:

• Ultraviolet rays from the sun
• Ultraviolet rays from fluorescent light bulbs
• Sulfa drugs, which make a person more sensitive to the sun
• Sun-sensitizing tetracycline drugs
• Penicillin or other antibiotic drugs
• Infection
• Cold or a viral illness
• Exhaustion
• Injury
• Emotional stress, including: divorce, illness, or other life complications
• Physical stress, including: surgery, physical harm, pregnancy, or giving birth


Because lupus is an autoimmune disease, it remains a mysterious condition that researchers haven’t quite figured out. It will take much more in-depth research before medical professionals truly understand what causes this autoimmune disease to occur.