[Association of CTLA-4 + 49A/G and CT60 gene polymorphism with type 1 diabetes and thyroid autoimmunity].
OBJECTIVE
To investigate the association of CTLA-4 + 49A/G and CT60 gene polymorphisms with type 1 diabetes (T1DM) and thyroid autoimmunity. Subjects Three hundred thirty-two T1DM patients and 476 controls were recruited in the study.


METHODS
The CTLA-4 + 49 A/G and CT60 polymorphisms of CTLA-4 gene were analyzed by polymerase chain reaction restriction fragment length polymorphism (PCR-RFLP) method. Thyroid peroxidase antibody (TPOAb) and thyroglobulin antibody (TGAb) were determined by radioimmunoassay. Glutamic acid decarboxylase antibody (GADA) and protein tyrosine phosphatase antibody (IA-2A) were measured by radioligand immunoassay.


RESULTS
(1) The CTLA-4 + 49 A/G polymorphism was significantly associated with T1DM complicated with thyroid autoimmunity (OR = 2.43, P < 0.01) and with T1DM alone (OR = 1.66, P < 0.05). (2) The CTLA-4 CT60 polymorphism was also significantly associated with T1DM complicated with thyroid autoimmunity (OR = 2.67, P < 0.01) and with T1DM alone (OR = 1.60, P = 0.02). (3) T1DM with thyroid autoimmunity was characterized by a significantly higher frequency of CTLA-4 CT60 GG genotype (77.8% vs 62.3%, P < 0.05) and GADA (77.8% vs 57.4%, P < 0.05) compared to the patients without thyroid antibodies.


CONCLUSIONS
CTLA-4 + 49 A/G and CT60 gene polymorphism confers genetic susceptibility to type 1 diabetes, particularly in patients with thyroid autoimmunity.
Jin
Ping
P
Diabetes Center, Metabolic Syndrome Research Center, Institute of Metabolism and Endocrinology, 2nd Xiangya Hospital, Central South University, Changsha, Hunan 410011, China.
Xiang
Bin
B
Lin
Jian
J
Huang
Gan
G
Zhou
Wei-Dong
WD
Zheng
Chao
C
Chao
Chen
C
Zhou
Zhi-Guang
ZG
D000293:Adolescent; D000328:Adult; D000368:Aged; D015703:Antigens, CD / Q000235:genetics*; D060908:CTLA-4 Antigen; D016022:Case-Control Studies; D002648:Child; D002675:Child, Preschool; D003922:Diabetes Mellitus, Type 1 / Q000150:complications / Q000235:genetics* / Q000276:immunology; D005260:Female; D005787:Gene Frequency; D020022:Genetic Predisposition to Disease; D005838:Genotype; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D008875:Middle Aged; D016884:Polyendocrinopathies, Autoimmune / Q000150:complications / Q000235:genetics / Q000276:immunology; D011110:Polymorphism, Genetic; D013967:Thyroiditis, Autoimmune / Q000150:complications / Q000235:genetics / Q000276:immunology*; D055815:Young Adult
D015703:Antigens, CD; D060908:CTLA-4 Antigen; C556706:CTLA4 protein, human