IL-13 Gene-1112 Single Nucleotide Polymorphisms in Taiwanese Periodontitis Patients

• Main Authors: Hsin-Lung Chuang, 莊欣龍
• Other Authors: Chi-Cheng Tsai
• Format: Others
• Language: zh-TW
• Published: 2008
• Online Access: http://ndltd.ncl.edu.tw/handle/60995093290058661017

碩士 === 高雄醫學大學 === 牙醫學研究所 === 96 === Background: Periodontitis is an infectious and inflammatory disease characterized by great amount of lymphocytes which accumulated at sites of periodontal lesion. The release of several cytokines results in the destruction of periodontium including alveolar bone eventually. In the pathogenic process of periodontal disease, Th2 cell cytokines such as IL-3, IL-4, IL-5, IL-6, IL-10 and IL-13 favorite the B-cell mediated humoral immunity. There are proofs supporting the claim that Th2-cytokines have the function for improving the symptom of inflammatory diseases. IL-13 has the anti-inflammatory effect and inhibits the secretion of TNF-α of circulating monocyte after released by Th2 cells. IL-13 induces fibrosis via promoting and activating the release of TGF-β1. IL-13 also inhibits osteoclast differentiation and bone resorption via the RANKL/RANK/OPG system. Recent study states that the IL-13 gene polymorphisms are associated with Graves’ disease of Japanese population. The aim of this study was to investigate the possible links between periodontitis and IL-13 -1112 genetic polymorphism in a Taiwanese population. Materials & Methods: Subjects of our study were divided into three groups, namely aggressive periodontitis (AgP=36), chronic periodontitis (CP=204), and healthy control (HC=95) according to the clinical periodontal examination or community periodontal index. The variants including gender, age, level of education, level of income, smoking status, alcoholic drink status and betel quid chewing status were also recorded. Genomic DNA was extracted from blood. Genotypes of IL-13─ 1112 were determined by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). The data were analyzed by χ2 test, one-way ANOVA and multiple logistic regression analyses. The risk for periodontitis associated with genotypes was calculated as the odds ratio (OR). Results: The prevalence of the CC, CT and TT genotypes was not differed significantly between groups (CP: 57.4%, 41.2% and 1.5%; AgP: 75.0%, 25.0% and 0.0%; HC: 54.7%, 43.2% and 2.1%). However, after adjustment for gender, age, level of education, level of income, smoking status, alcoholic drink status and betel quid chewing status, the prevalence of the CC genotype compared with the CT/TT genotypes was significantly higher in AgP. The crude OR and adjusted OR for -1112 CC versus CT/TT in AgP group were 2.48 (p=0.034) and 6.21 (p=0.006) respectively. There was no difference of the genotype frequency in CP group (p>0.05). The adjusted OR was 4.74 (p=0.028) for nonsmoking AgP group compared with nonsmoking HC group. The genotype of the IL-13 polymorphism did not differ between smoking AgP and smoking HC groups (p>0.05). Conclusions: The results of this study suggested that the CC genotype of the IL-13-1112 C/T polymorphism seems to be associated with an increased risk for aggressive periodontitis in a Taiwanese population. The CC genotype effect was overwhelmed by smoking habit in AgP patients. Further research is necessary to prove the polymorphisms to have a functional effect.