A promoter polymorphism of tumor necrosis factor α associated with systemic lupus erythematosus in African-Americans

Objective. The polymorphic tumor necrosis factor alpha (TNF alpha) gene encodes a cytokine involved in inflammation, angiogenesis, and apoptosis. One polymorphic variant is associated with increased production of TNF alpha. This study examined the frequency of this polymorphic variant in African-American patients with systemic lupus erythematosus (SLE) compared with controls. Methods. We determined the gene frequency of the polymorphic variant of TNF alpha in an African-American SLE patient population and in a geographically matched African-American control population. Results. The gene frequency of the TNF alpha -308A polymorphism was higher in the African-American SLE population than in the control population. This relationship was independent of major histocompatibility complex DR alleles. Conclusion. The TNF alpha -308A polymorphism is associated with an increased risk of SLE in African-Americans.