To explore whether having the mutant tumor necrosis factor (TNF)2 (G-308*A) and TNFA-A (G-238*A) alleles in the TNF-alpha gene promotor region is higher in women with endometriosis, we determined the respective genotype and allele frequencies in a retrospective case-control study. Polymerase chain reaction was performed to identify the G-308A and G-238A promotor polymorphisms in 92 women with surgically and histologically confirmed endometriosis. A series of 69 healthy women without a history of endometriosis served as clinical controls. The allele frequencies of the TNF2 polymorphism were 0.13 and 0.16 in women with endometriosis and in the control group, respectively, and the frequencies of the TNFA-A polymorphisms in women with endometriosis and in the control group were 0.04 and 0.05, respectively, with no significant difference between the study and control groups. The TNF2 polymorphism was present in the homozygous form (TNF(2/2)) in 4.3% of women with endometriosis and in 2.9% of controls (P=.7). No TNFA-A homozygotes (TNFA(A/A)) were detected. We studied TNF-alpha promotor gene variants among women with endometriosis and found that having the G-308A TNF-alpha and the G-238A TNF-alpha polymorphism was not associated with endometriosis in a white population.