IkBα promoter polymorphisms in patients with primary Sjogren's syndrome

Introduction To investigate the association of IkB alpha promoter polymorphisms with the development of primary Sjogren's syndrome in Taiwan, 98 patients with primary Sjogren's syndrome and 110 unrelated healthy controls were enrolled in this study. Materials and Methods The I kappa B alpha -881 A/G, I kappa B alpha -826 C/T, I kappa B alpha -550 A/T, I kappa B alpha -519 C/T, and I kappa B alpha -297 C/T polymorphisms were determined by the methods of polymerase chain reaction/restriction fragment length polymorphism. Discussion This study demonstrated that the genotype frequencies of I kappa B alpha -826 C/T and I kappa B alpha -826 T/T, in comparison with that of I kappa B alpha -826 C/C, were significantly higher in the patients with primary Sjogren's syndrome than in the controls. The allele frequency of I kappa B alpha -881 G was significantly decreased in the patients with primary Sjogren's syndrome compared with that of the controls. In contrast, the allele frequency of I kappa B alpha -826 T was significantly higher in the patients with primary Sjogren's syndrome than in the controls. The similar findings could also be found in the allele carriage frequencies. The patients with primary Sjogren's syndrome had lower allele carriage frequencies of I kappa B alpha -881 G and I kappa B alpha -826 C, and a higher allele carriage frequency of I kappa B alpha -826 T. We also found that the estimated haplotype frequency of I kappa B alpha -881A-826T-550A-519C-297C was significantly increased in the patients with primary Sjogren's syndrome in comparison with that of the controls. Discussion This study demonstrated that the IkB alpha -826T allele and IkB alpha -881A-826T-550A-519C-297C haplotype were associated with susceptibility to primary Sjogren's syndrome in Taiwan. However, these findings may not be disease-specific but may be related to inflammatory responses.