Xiao-Ping Ye1,2, Fei-Fei Yuan1,2, Le-Le Zhang2, Yu-Ru Ma2, Man-Man Zhang2, Wei Liu2, Feng Sun2, Jing Wu2, Meng Lu2, Li-Qiong Xue2, Jing-Yi Shi1, Shuang-Xia Zhao2, Huai-Dong Song1,2, Jun Liang3,4, Cui-Xia Zheng2. 1. State Key Laboratory of Medical Genomics, Shanghai Institute of Endocrinology and Metabolism, Ruijin Hospital affiliated to Shanghai Jiaotong University School of Medicine, Shanghai 200025, China. 2. Research Center for Clinical Medicine, Department of Respiration and Endocrinology, The Ninth People's Hospital Affiliated to Shanghai Jiaotong University School of Medicine, Shanghai 200011, China. 3. Department of Endocrinology, The Central Hospital of Xuzhou Affiliated to Xuzhou Medical College, Xuzhou, Jiangsu Province 221109, China; and. 4. Xuzhou Clinical School of Xuzhou Medical College, The Affiliated XuZhou Hospital of Medical College of Southeast University, Xuzhou, Jiangsu Province 221009, China.
Abstract
Context: Graves disease (GD) is a common autoimmune disease triggered by genetic predisposition and environmental factors. However, the mechanisms of interaction between genetic and environmental factors contributing to the development of GD remain unknown. Objective: We aimed to identify GD susceptibility variants and genes on Xq21.1 locus and interpret the contribution of interaction between genetic predisposition on Xq21.1 and environmental factors to GD. Design: We performed refining study on Xq21.1 in a 2-stage study and carried out expression quantitative trait locus analysis of the best association signal with GD. Setting and Participants: A total of 4316 GD patients and 4374 sex-matched controls were collected from the Chinese Han population by cooperation with multiple hospitals. Results: We identified that rs3827440 or its linkage single nucleotide polymorphisms (SNPs) were probably the causal variant in the Xq21.1 locus, with the most substantial association with GD in our combined cohorts (P = 2.45 × 10-15). The genotypes of rs3827440 were correlated with the expression of ITM2A in monocytes and peripheral blood mononuclear cells (PBMCs) from healthy volunteers. Notably, the expression of ITM2A in monocytes after lipopolysaccharide (LPS) and interferon-γ (INF-γ) stimulation showed substantial difference among the volunteers that carried different genotypes of rs3827440 (P = 9.40 × 10-7 and P = 1.26 × 10-5 for 24 hours' LPS and INF-γ stimulation, respectively). Moreover, ITM2A expression was significantly decreased in PBMCs from untreated GD patients than that from controls. Conclusion: The results suggest that ITM2A might be a susceptibility gene for GD in the Xq21.1 locus, and environmental factors, such as viral and bacterial infections, probably contribute to GD pathogenesis by interacting with the risk SNP rs3827440 mediating the regulation of ITM2A expression.
Context:Graves disease (GD) is a common autoimmune disease triggered by genetic predisposition and environmental factors. However, the mechanisms of interaction between genetic and environmental factors contributing to the development of GD remain unknown. Objective: We aimed to identify GD susceptibility variants and genes on Xq21.1 locus and interpret the contribution of interaction between genetic predisposition on Xq21.1 and environmental factors to GD. Design: We performed refining study on Xq21.1 in a 2-stage study and carried out expression quantitative trait locus analysis of the best association signal with GD. Setting and Participants: A total of 4316 GDpatients and 4374 sex-matched controls were collected from the Chinese Han population by cooperation with multiple hospitals. Results: We identified that rs3827440 or its linkage single nucleotide polymorphisms (SNPs) were probably the causal variant in the Xq21.1 locus, with the most substantial association with GD in our combined cohorts (P = 2.45 × 10-15). The genotypes of rs3827440 were correlated with the expression of ITM2A in monocytes and peripheral blood mononuclear cells (PBMCs) from healthy volunteers. Notably, the expression of ITM2A in monocytes after lipopolysaccharide (LPS) and interferon-γ (INF-γ) stimulation showed substantial difference among the volunteers that carried different genotypes of rs3827440 (P = 9.40 × 10-7 and P = 1.26 × 10-5 for 24 hours' LPS and INF-γ stimulation, respectively). Moreover, ITM2A expression was significantly decreased in PBMCs from untreated GDpatients than that from controls. Conclusion: The results suggest that ITM2A might be a susceptibility gene for GD in the Xq21.1 locus, and environmental factors, such as viral and bacterial infections, probably contribute to GD pathogenesis by interacting with the risk SNP rs3827440 mediating the regulation of ITM2A expression.