Lupus is a systemic autoimmune disease that has some genetic factors. It is also tied to environmental risk, which may determine whether people actually ever manifest the illness. These environmental factors may also play a role in the degree to which lupus may affect a person’s life and mortality. Thus while some with lupus may have a genetic predisposition for the disease, not all with genetic factors will get lupus.

Lupus is most common in African populations, affecting approximately three times more people than in the rest of racial populations combined. This factor alone suggests genetic origins of lupus, especially when relatively small groups of people seem to manifest lupus on a more regular basis.

A 1997 study by the National Institute of Health evaluated a form of lupus that causes a high rate of morbidity due to deterioration of the kidneys. The research group examined was a population of African Americans. One specific gene was found to be most indicative in determining lupus involving the kidneys, also called lupus nephritis. In almost all cases of those studied with the condition, a specific gene was shown to be a weaker version than that present in the participants who did not have lupus.

Though some who did not have lupus had the weaker gene, they had not developed lupus nephritis. This finding suggests that genetics are only a partial factor in determining who will get lupus. Environmental conditions may have some effect as well.

Certain types of lupus do tend to occur more frequently in families. This is particularly the case among female siblings. Yet even with extensive studies, scientists cannot positively conclude that lupus is “genetic” and that a person will get lupus if others in their family have it. However, a 2002 study published in The Annals of Rheumatic Disease concludes that genetics play at least some part in development of the disease.

Since some people with genetic predisposition for lupus do not contract the condition, it is important to evaluate what environmental factors are indicated in disease prevention. While a few genes have been studied as factors for lupus, more genes may be involved that have not been identified. Researchers often find that there can be several genes responsible for a condition. Those genes that are, as yet unknown, may also help determine to what degree environment and genetics are factors in developing lupus.