Polymorphisms of Dioxin Receptor Complex Components and Detoxification-Related Genes Jointly Confer Susceptibility to Advanced-Stage Endometriosis in the Taiwanese Han Population Cheng-Hsuan Wu 1,2,3 , Chao-Yu Guo 4 , Jyuer-Ger Yang 2 , Horng-Der Tsai 2 , Yu-Jun Chang 5 , Pei-Chien Tsai 6 , Chao-Chin Hsu 7 , Pao-Lin Kuo 8 1 Institute of Medicine, Chung Shan Medical University, Taichung, Taiwan; 2 Department of Obstetrics and Gynecology, Changhua Christian Hospital, Changhua, Taiwan; 3 College of Health Sciences, Chang Jung Christian University, Tainan, Taiwan; 4 Department of Environmental and Occupational Health, National Yang Ming University, Taipei, Taiwan; 5 Epidemiology and Biostatistics Center, Changhua Christian Hospital, Changhua, Taiwan; 6 Department of Biomedical Science and Environmental Biology, Kaohsiung Medical University Hospital, Kaohsiung, Taiwan; 7 Department of Obstetrics & Gynecology, Shuang Ho Hospital, Taipei Medical University, Taipei, Taiwan; 8 Department of Obstetrics and Gynecology, Cheng Kung University Hospital, Tainan, Taiwan Introduction Endometriosis is defined as the presence of endome- trial tissue outside the uterine cavity. The prevalence of endometriosis has been reported to be as high as 6–10% of women, and up to 50% of women who underwent laparoscopy for pelvic pain or infertil- ity. 1,2 The most common symptoms associated with endometriosis include dysmenorrhea, chronic pelvic pain, and infertility. Although the etiology of endo- Keywords Detoxification-related genes, endometriosis Correspondence Chao-Chin Hsu, Department of Obstetrics and Gynecology, Shuang Ho Hospital, Taipei Medical University, 291 Jhongjheng Rd., Jhonghe District, New Taipei City 23561, Taiwan. E-mail: tube2363808@gmail.com Pao-Lin Kuo, Department of Obstetrics and Gynecology, National Cheng Kung University Hospital, 138 Sheng-Li Road, Tainan 704, Taiwan. E-mail: paolink@mail.ncku.edu.tw Submitted July 7, 2011; accepted September 20, 2011. Citation Wu C-H, Guo C-Y, Yang J-G, Tsai H-D, Chang Y-J, Tsai P-C, Hsu C-C, Kuo P-L. Polymorphisms of dioxin receptor complex components and detoxification-related genes jointly confer susceptibility to advanced-stage endometriosis in the Taiwanese Han population. Am J Reprod Immunol 2012; 67: 160–168 doi:10.1111/j.1600-0897.2011.01077.x Problem To establish a multilocus model for studying the effect of dioxin receptor complex components and detoxification-related enzymes on advanced endometriosis. Method of study Six single-nucleotide polymorphisms (SNPs) and two deletion polymor- phisms from eight genes (CYP1A1, CYP1B1, GSTM1, GSTT1, GSTP1, AhR, ARNT, and AhRR) were genotyped. Results In the single SNP analysis, GSTM1 null type and AhRR variant type were associated with a significantly increased risk of endometriosis [odds ratio (OR) = 2.38 and 2.45, respectively]. Using multiple SNPs in the logistic regression for covariates, wild-type AhR and mutant AhRR com- bination was significantly higher in patients (67.8%) than in controls (48.0%) (OR = 2.76). On the other hand, mutant AhRR in combination with GSTM1 null genotype was significantly higher in patients (35.5%) than in controls (19.3%) (OR = 6.12). Conclusion Polymorphisms of dioxin receptor complex components and detoxifica- tion-related genes jointly confer susceptibility to advanced-stage endo- metriosis in the Taiwanese Han population. ORIGINAL ARTICLE American Journal of Reproductive Immunology 67 (2012) 160–168 160 ª 2011 John Wiley & Sons A/S