Although the role of many polymorphisms of genes related to toxins’ metabolism has been extensively investigated regarding the susceptibility to thyroid cancer, their influence in thyroid autoimmune diseases risk is still largely unknown. Hence, this study was designed to assess the influence of GSTT1, GSTM1, GSTP1, CYP1A1 and 72TP53 polymorphic inheritance on the susceptibility to Graves' disease and to its response to the treatment.