TNF and systemic lupus erythematosus: Background/Objectives: A case-control study was conducted to determine the association of the −238 G>A and −308 G>A TNF-alpha (TNFA) promoter polymorphisms with mRNA and protein expression in 180 Systemic Lupus Erythematosus (SLE) patients and 186 control subjects (CS) from western Mexico.