CTLA-4+49 A/G polymorphism and antiglutamic acid decarboxylase antibody-associated encephalopathy in Taiwanese children

BackgroundAnti-glutamic acid decarboxylase antibodies are associated with encephalopathy, an autoimmune central nervous system inflammatory disease. The cytotoxic T-lymphocyte-associated antigen 4 (CTLA-4)+49 A/G polymorphism has been shown to confer genetic susceptibility to positive anti-glutamic acid decarboxylase antibodies in patients with type 1 diabetes mellitus in Japan. We aimed to investigate the association of the CTLA-4+49 A/G (rs231775) polymorphism in Taiwanese children with anti-glutamic acid decarboxylase antibody-associated encephalopathy.MethodsThis was a case-control study from July 2011 to June 2012 performed at Chang Gung Children’s Hospital in Taiwan. Genotyping of the CTLA-4+49 A/G polymorphism was performed by polymerase chain reaction-restriction fragment length polymorphism.ResultsSeventeen patients with anti-glutamic acid decarboxylase antibody-associated encephalopathy and 97 controls were enrolled. The genotype, allele and carrier frequencies of the CTLA-4+49 A/G polymorphism were equally distributed in the patients and controls, with no significant differences between the two groups. In addition, we found a positive trend between the level of anti-glutamic acid decarboxylase antibodies and the G allele of the CTLA-4+49 A/G polymorphism, although this trend was not statistically significant.ConclusionsOur results suggest that the CTLA-4+49 A/G (rs231775) polymorphism does not confer an increased susceptibility to anti-glutamic acid decarboxylase antibody-associated encephalopathy in Taiwanese children.