Investigation of interleukin-13 gene polymorphisms in individuals with chronic and generalized aggressive periodontitis in a Taiwanese (Chinese) population

BACKGROUND AND OBJECTIVE: The interleukin-13 (IL-13) -1112 C/T polymorphisms have been analyzed previously in a North European population of patients with aggressive periodontitis. The present study was carried out to investigate the association of polymorphisms in the IL-13 gene with susceptibility to periodontitis in a Taiwanese population. MATERIAL AND METHODS: The genotyping of IL-13 -1112 C/T polymorphisms in 60 patients with aggressive periodontitis, 204 patients with chronic periodontitis and 95 healthy controls was carried out using the polymerase chain reaction-restriction fragment length polymorphism technique. Genotypes and allele frequencies among study groups were compared using Fisher's exact test (p < 0.05). Pearson's chi-square test was used for analysis of the Hardy-Weinberg equilibrium. RESULTS: The distributions of CC genotypes and C alleles between patients with aggressive periodontitis and healthy controls were significantly different (p = 0.034 and 0.046). After adjustment for age, gender, betel nut chewing and smoking status using logistic regression analysis, the odds ratio (OR) was 6.45 [95% confidence interval (CI) = 1.99-23.72, p = 0.003] for aggressive periodontitis. However, the CC genotype was only significantly associated with the risk of aggressive periodontitis in the nonsmoking group (OR = 4.48, 95% CI = 1.31-16.93, p = 0.020). CONCLUSION: The CC genotype or C allele appears to increase the risk of developing aggressive periodontitis in Taiwanese subjects.