Tumor Necrosis Factor (TNF)-TNF Receptor Gene Polymorphisms and Their Serum Levels in Korean Women with Endometriosis

Problem The aim of this study was to investigate the relationship between the polymorphisms of the tumor necrosis factor-alpha (TNF-alpha) and TNF receptor (TNFR) genes and serum levels of TNF-alpha and its soluble receptor (sTNFR) in Korean women with endometriosis. Method of study The TNF-alpha C(-857)T, C(-863)A and T(-1031)C, and TNFR1 A(36)G, TNFR2 T(676)G, A(1663)G, T(1668)G and C(1690)T polymorphisms, and serum levels of TNF-alpha, sTNFR1, and sTNFR2 were analyzed in women with (n = 105) and without endometriosis (n = 101). Results Serum sTNFR1 and sTNFR2 levels were significantly higher in women with endometriosis than in those without endometriosis, whereas no difference in serum TNF-alpha level was noted. Single polymorphisms of TNF-alpha and TNFR genes were not significantly different between the two groups. The frequencies of the TNF-alpha T/C/C haplotype allele and the TNFR2 G/G/T haplotype allele were significantly decreased in women with endometriosis compared to women without endometriosis. Women carrying at least one copy of the TNFR2 T/G/T and /or G/G/C haplotype allele had an approximately two times higher risk of endometriosis than women without these haplotype alleles. Conclusion The haplotype alleles of the TNF-alpha and TNFR2 gene polymorphisms are genetic factors associated with endometriosis, and circulating sTNFR rather than TNF-alpha, may be involved in the development of endometriosis in Korean women.