No association between Fas A/G polymorphism and therapeutic effects induced by methimazole treatment for Graves' disease in Northern Chinese. 
Fas gene, which is related to apoptosis, influences the clinical remission of Graves' disease (GD).  This study was performed to determine whether the Fas gene promoter polymorphism at position-670 is associated with different efficacy in GD patients treated with methimazole (MMI).  Serum levels of thyroid hormone, sFas and thyrotropic-stimulating hormone receptor antibodies (TRAb) were evaluated as therapeutic efficacy parameters before and after 18-month treatment with MMI in a total of 115 subjects of North China.  At the end of the follow-up study, patients were categorized into an effective group (group A) and an ineffective group (group B) according the level of thyroid hormone.  Similar to the changes of thyroid hormone, the reductions of sFas and TRAb were significantly different in the two groups (P < 0.05).  Meanwhile, we detected that Fas promoter-670 A/G polymorphism existed in the GD patients of North China.  We studied the frequencies of genotypes and alleles of the A/G polymorphism in different groups.  However, there was no association between different efficacy and Fas promoter polymorphism in patients with GD.