Influence of Interleukin 10 Promoter Polymorphisms in Susceptibility to Giant Cell Arteritis in Northwestern Spain

BLANCA RUEDA, BEGOÑA ROIBAS, JAVIER MARTIN, and MIGUEL A. GONZALEZ-GAY

ABSTRACT.

Objective. Proinflammatory cytokines such as interferon-g (IFN-g) play an important role in the pathogenesis of giant cell arteritis (GCA). Interleukin 10 (IL-10) is a Th2 cytokine with a suppressor effect on IFN-g production. We assessed the influence of functional IL-10 gene promoter polymorphisms in susceptibility to GCA in individuals from Northwestern Spain.

Methods. One hundred three patients with biopsy-proven GCA and 226 matched controls from the Lugo region of Northwest Spain were genotyped for IL-10 –1082 G/A (rs1800896) and –592 C/A (rs1800872) promoter single nucleotide polymorphisms (SNP) by Taqman 5' allelic discrimination assay using Taqman predesigned SNP genotyping assays (numbers C_1747360_10 and C_1747363_10, respectively).

Results. A significant difference in the distribution of –1082 G/A genotypes between GCA patients and controls was observed (p = 0.034). It was mainly due to a decreased number of GCA patients carrying the –1082 A/A genotype (23.3%) compared with controls (36.7%) [p = 0.01, corrected p (p_c) = 0.03; OR 0.53, 95% CI 0.31– 0.90]. In addition, haplotype analysis showed that the ATA haplotype frequency was slightly decreased (p = 0.05, p_c = 0.2; OR 0.6, 95% CI 0.4–1.0), whereas the uncommon GTA haplotype was significantly increased in GCA patients compared with controls (p = 0.00005, p_c = 0.0002; OR 8.7, 95% CI 2.2–34.8).

Conclusion. Our results suggest a potential implication of IL-10 –1082 promoter polymorphism in susceptibility to GCA in Northwestern Spain. (First Release June 1 2007; J Rheumatol 2007:34:1535-9)

Key Indexing Terms:

GIANT CELL (TEMPORAL) ARTERITIS
TEMPORAL ARTERY BIOPSY
INTERLEUKIN 10
GENE POLYMORPHISMS

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From the Consejo Superior de Investigaciones Cientificas (CSIC), Granada; and Division of Rheumatology, Hospital Xeral-Calde, Lugo, Spain.

Dr. Gonzalez-Gay and Dr. Martin share senior authorship in this study.

B. Rueda, PhD; B. Roibas, BSc; J. Martin, MD, PhD, Consejo Superior de Investigaciones Cientificas; M.A. Gonzalez-Gay, MD, PhD, Division of Rheumatology, Hospital Xeral-Calde.

Address reprint requests to Dr. M.A. Gonzalez-Gay, Rheumatology Division, Hospital Xeral-Calde, c) Dr. Ochoa s/n, 27004, Lugo, Spain. E-mail: miguelaggay@hotmail.com

Accepted for publication March 12, 2007.

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