Department of Immunology, School of Medicine, Tehran University of Medical Sciences, Tehran, Iran.
J Clin Immunol. 2010 Mar;30(2):268-71. doi: 10.1007/s10875-009-9356-y. Epub 2009 Dec 11.
Cytotoxic T-lymphocyte antigen 4 (CTLA-4) is a costimulatory molecule expressed by activated T cells. This study was performed to investigate the allele and genotype frequencies of CTLA4 gene polymorphisms in Iranian patients with ankylosing spondylitis (AS).
One hundred and fifty-seven patients with AS and 103 controls were included in this study. Polymorphisms of CTLA4 gene at positions +49 (in exon 1), -318, and -1,147 (in the promoter region) were studied on the genomic DNA using PCR restriction fragment-length polymorphism method.
The frequencies of the T allele at position -1147 in the patients with AS was significantly increased in comparison with the control group (11% vs. 5%, P = 0.004); whereas the frequencies of C allele at the same position were significantly decreased in the patient group (89% vs. 95%, P = 0.004). Comparison of genotype frequencies at this position showed that the frequency of CT genotype in comparison with other genotypes was overrepresented in the patient group (20% vs. 8%, P = 0.012), while the CC genotype in comparison with other genotypes was decreased (79% vs. 91%, P = 0.012). There was no significant difference on frequencies of genotypes at the positions -318 and +49.
This study could suggest an association between specific allele in the promoter region of CTLA4 gene and AS disease.
细胞毒性 T 淋巴细胞相关抗原 4（CTLA-4）是一种表达于活化 T 细胞的共刺激分子。本研究旨在探讨 CTLA4 基因多态性在伊朗强直性脊柱炎（AS）患者中的等位基因和基因型频率。
本研究纳入了 157 例 AS 患者和 103 例对照。采用 PCR 限制性片段长度多态性方法，对 CTLA4 基因在位置+49（外显子 1）、-318 和-1,147（启动子区域）的多态性进行了研究。
与对照组相比，AS 患者中 CTLA4 基因-1147 位置的 T 等位基因频率明显升高（11% vs. 5%，P=0.004）；而同一位置的 C 等位基因频率在患者组中明显降低（89% vs. 95%，P=0.004）。比较该位置的基因型频率发现，与其他基因型相比，CT 基因型在患者组中的频率更高（20% vs. 8%，P=0.012），而 CC 基因型与其他基因型相比则减少（79% vs. 91%，P=0.012）。-318 和+49 位置的基因型频率无显著差异。
本研究提示 CTLA4 基因启动子区域的特定等位基因与 AS 疾病之间存在关联。
