title: Analysis of CD28 and CTLA-4 gene polymorphisms in Turkish patients with Behcet's disease.
abstract: In this study we aimed to investigate IVS3 +17T/C single nucleotide polymorphism (SNP) of CD28 gene, +49A/G and -318C/T SNPs of CTLA-4 gene in patients with Behçet's disease (BD) and their potential association to the main clinical features of the disease. These polymorphisms were investigated in a Turkish population of 123 patients with BD and 179 healthy controls, by using PCR-RFLP technique. HLA-B*51 genotype was also studied in both groups by using PCR-SSP. The frequency of IVS3 +17TC genotype of the CD28 gene was significantly increased in BD patients compared to controls (43.6% vs. 31.2%, OR = 1.663, 95% CI = 1.033-2.679, P = 0.039). CTLA-4 +49GG genotype frequency was found to be significantly lower in patients with BD than those of healthy controls (4% vs. 10.6%, OR = 0.357, 95% CI = 0.130-0.983, P = 0.05). Genotype and allele frequencies of the CTLA-4-318C/T polymorphism between the BD and healthy control groups were not significantly different (12.2% vs. 10.6%, OR = 1.170, 95% CI = 0.570-2.402, P = 0.713). There were no associations between the studied polymorphisms and the main clinical features of BD. The frequencies of HLA-B*51 were 60.3% and 30.7% in BD and control groups, respectively (OR = 3.429, 95% CI = 2.115-5.559, P = 0.0001). Association between HLA-B*51 and each studied polymorphism did not reach to significant levels (OR = 0.479, 95% CI = 0.228-1.004, P = 0.064 for CD28 IVS3 +17TT genotype; OR = 2.180, 95% CI = 1.025-4.639, P = 0.061 for TC genotype; OR = 1.570, 95% CI = 0.870-2.836, P = 0.146 for C allele). These results may suggest that CD28 IVS3 +17TC genotype may be a risk factor for the development of BD, on the contrary CTLA-4 +49GG genotype may be protective in the studied Turkish population.
authors.affiliation: Department of Rheumatology-Immunology, Cukurova University Faculty of Medicine, Balcali, Tr-01330, Adana, Turkey. gamgul@cu.edu.tr
authors.forename: R
authors.initials: R
authors.lastname: Gunesacar
authors.forename: E
authors.initials: E
authors.lastname: Erken
authors.forename: B
authors.initials: B
authors.lastname: Bozkurt
authors.forename: H T
authors.initials: HT
authors.lastname: Ozer
authors.forename: S
authors.initials: S
authors.lastname: Dinkci
authors.forename: E G
authors.initials: EG
authors.lastname: Erken
authors.forename: Z
authors.initials: Z
authors.lastname: Ozbalkan
mesh_terms: D015703:Antigens, CD / Q000235:genetics*; D000943:Antigens, Differentiation / Q000235:genetics*; D001528:Behcet Syndrome / Q000235:genetics*; D018106:CD28 Antigens / Q000235:genetics*; D060908:CTLA-4 Antigen; D005260:Female; D020022:Genetic Predisposition to Disease; D006801:Humans; D008297:Male; D020641:Polymorphism, Single Nucleotide; D014421:Turkey
chemical_list: D015703:Antigens, CD; D000943:Antigens, Differentiation; D018106:CD28 Antigens; D060908:CTLA-4 Antigen; C556706:CTLA4 protein, human