Correlation between gene polymorphism ofcytotoxic T lymphocyte associated antigen-4 andGraves disease in Qinghai Tibetan

Objective To investigate the correlation between gene polymorphism of cytotoxic T lymphocyte associated antigen-4(CTLA-4)and Graves disease(GD)in Qinghai Tibetan.Methods Using retrospective analysis methods,totally 130 cases of GD were selected randomly from June 2012 to November 2016 in the People's Hospital of Qinghai Province;meanwhile,110 normal control cases were selected randomly from Qinghai Tibetan.Then the genotype and allele of CTLA-4 were detected by the method of polymerase chain reaction restriction fragment length polymorphism(RFLP-PCR).Results The distribution of CTLA-4 genotype frequencies(AA,AG,GG)was different between the normal control cases and GD in Qinghai Tibetan [6.2%(8/130)vs 26.4%(29/110),50.0%(65/130)vs 58.2%(64/110),43.8%(57/130)vs 15.4%(17/110),X^2=32.105,P<0.05].Allele(A,G)frequencies were compared between GD and control,the differences were statistically significant [31.2%(81/260)vs 55.5%(122/220),68.8%(179/260)vs 44.5%(98/220),X^2=28.834,P<0.05].Conclusion Polymorphisms of CTLA-4 exon 1(49A/G)genotype and allele are closely correlated with GD in Qinghai Tibetan.