Table 3.

Summary of genetic polymorphism studies with no association or significance

Reference	Sample size	Involved genes	Population	Summary
Matsuzaka et al., 2012[36]	Case: 100	ESR1 gene	Japanese	No statistically significant differences were noted in the SNP allele frequencies and genotypes between the cases and controls in ESR1 gene. ESR1 gene polymorphisms are not significantly associated with the development of endometriosis
	Control: 143
Chae et al., 2010[37]	Case: 390	ICAM-1 gene	Korean	The K469E and G241R polymorphisms in the ICAM-1 gene and the C-634G polymorphism in the IL-6 gene may not be genetic factors related to susceptibility to advanced-stage endometriosis
	Control: 351	IL-6 gene
Lee et al., 2009[38]	Case: 237	IL-2R β gene	Korean	The C627T polymorphism of the IL-2R β gene is not associated with advanced stage endometriosis in a Korean population
	Control: 164
Kim et al., 2008[39]	Case: 105	VEGF genes	Korean	Endostatin G (4349) A and VEGF C (936) T polymorphisms was not associated with endometriosis
	Control: 101
				Serum endostatin levels (but not VEGF levels) were negatively correlated with the development of endometriosis, specifically in early-stage endometriosis patients
Hur et al., 2005[40]	Case: 194	GSTM1 gene GSTT1 gene	Korean	No association was noted between the genetic polymorphisms of GSTM1, GSTT1, and GSTP1 with the development of endometriosis in Korean women
	Control: 259
		GSTP1 gene

SNP: Single- nucleotide polymorphism, TNF-: Tumor necrosis factor- alpha, GST: Glutathione-S-transferases