XRCC1 632 as a candidate for cancer predisposition via a complex interaction with genetic variants of base excision repair and double strand break repair genes.

Aim: The DNA repair system safeguards integrity of DNA. Genetic alterations force the improper repair which in conjugation with other factors ultimately results in carcinogenesis. Materials & methods: PCR-restriction fragment length polymorphism was used for genotyping, which was followed by statistical analysis using logistic regression analysis, multifactor dimensionality reduction and classification and regression analysis tree, elaborating the association with lung cancer subjects. Results: Combination of XRCC1 632 and OGG1326 showcased a high risk of eightfold (odds ratio: 7.92; 95% CI: 2.68-23.4; p = 0.0002; false discovery rate (FDR) p = 0.002). Similarly, XRCC1 632 and MUTYH 324 (odds ratio: 5.07; 95% CI: 2.6-9.67; p < 0.0001; FDRp = 0.002) had a high risk. Multifactor dimensionality reduction analysis revealed five factor model as the best model with prediction error of 0.37 (p = 0.02). Conclusion: There was a clear indication that high order interactions were major role players in the study.

Interleukin gene polymorphisms in chronic periodontitis: A case-control study in the Indian population.

OBJECTIVE: The aim of the present study was to investigate the possible association between seven Interleukin (IL) gene polymorphisms and their interaction with the chronic inflammatory oral disease, chronic periodontitis in Indian population. DESIGN: A total of 357 study subjects (157 with chronic periodontitis and 200 with healthy control) were genotyped for IL1A -889C/T (rs1800587), IL1B -31C/T (rs1143627), IL1B -511A/G (rs16944), IL1B + 3954C/T (rs1143634), IL2 -330 T/G (rs2069762), IL4 -33C/T (rs2070874), IL6 -597 G/A (rs1800797), IL8 -251A/T (rs4073), IL10 -819C/T (rs1800871), IL10 -592A/C (rs1800872) and IL13 -1111C/T (rs1800925). Statistical analysis was performed using the statistical software package SPSS v16. SNPassoc and Multifactor Dimensionality Reduction algorithm v3.0.2. RESULTS: We found that the statistically significant association of IL1A-889C/T (rs1800587), IL1B -31C/T (rs1143627), IL1B -511A/G (rs16944) and IL1B + 3954C/T (rs1143634) gene polymorphisms with increased susceptibility of chronic periodontitis. The best gene-gene interaction model was IL1B(-31C/T) X IL1B(+3954C/T) X IL10(-819C/T) with 10/10 cross validation consistency. The variant allele of IL1A, IL1B, IL10 and IL13 were seemed to be linked with chronic periodontitis increased susceptibility. The results of this study also indicate that epidemiological factors especially oral habits also play an important role in the development of chronic periodontitis. CONCLUSIONS: This study concludes IL1A -889C/T (rs1800587), IL1B -31C/T (rs1143627), IL1B -511A/G (rs16944), IL1B + 3954C/T (rs1143634), IL10 -819C/T (rs1800871), IL10 -592A/C (rs1800872) and IL13 -1111C/T (rs1800925) gene polymorphisms are significantly associated with chronic periodontitis. This work also infers that the best interactive model comprised of IL1B and IL10 polymorphisms cumulatively increase the risk of chronic periodontitis.