Is Lupus a Hereditary Disease?

Systemic Lupus Erythematosus (SLE) is not simply passed down through generations, although family genetics do play a role in determining whether or not you will have lupus. In fact, only 10% of lupus patients have an immediate family member (sibling, child or parent)  or “second degree” family member (aunt, uncle, cousin) who have lupus. This means that 90% of lupus patients do not have a family member with active lupus disease, indicating that lupus is not a hereditary disease. There are even cases where one sibling in a pair of identical twins has lupus and the other does not. This has lead researches to believe that there is more than just genetics involved in the development of the lupus disease. Environmental factors play an important role in causing lupus.

Environmental Triggers

If a person has a genetic predisposition towards lupus, then there is a possibility that lupus can be triggered at some point, causing symptoms such as hair loss or a malar rash. It is believed that environmental factors such as other diseases, stress, hormones and others can cause lupus symptoms to flare. Some other common environmental triggers are:

  • Exposure to sunlight
  • Prescription medication
  • Infections

DNase1 Enzyme, Lupus and Hereditary Disease

Some studies have shown that a key enzyme called DNase1 may be the cause of lupus developing in a patient. The normal role of DNase1 is to destroy what has been termed “garbage DNA” and other cellular waste by cutting it up for disposal by the body. Researchers believe that when the DNase1 enzyme fails to discard these dying cells, it may contribute to lupus. So, what causes the enzyme to not function properly? It is possible that genetic mutation could cause the enzyme to act improperly. So, if a genetic mutation is passed from parent to child, and such a genetic mutation potentially causes lupus, then lupus is in a way a hereditary disease.