CCDC26 Gene Polymorphism and Glioblastoma Risk in the Han Chinese Population

Background: Glioblastoma (GBM) is an immunosuppressive tumor whose median survival time is only 12-15 months, and patients with GBM have a uniformly poor prognosis. It is known that heredity contributes toformation of glioma, but there are few genetic studies concerning GBM. Materials and
Methods: We genotypedsix tagging SNPs (tSNP) in Han Chinese GBM and control patients. We used Microsoft Excel and SPSS 16.0statistical package for statistical analysis and SNP Stats to test for associations between certain tSNPs and risk ofGBM in five different models. ORs and 95%CIs were calculated for unconditional logistic-regression analysis withadjustment for age and gender. The SHEsis software platform was applied for analysis of linkage disequilibrium,haplotype construction, and genetic associations at polymorphism loci.
Results: We found rs891835 in CCDC26to be associated with GBM susceptibility at a level of p=0.009. The following genotypes of rs891835 were foundto be associated with GBM risk in four different models of gene action: i) genotype GT (OR=2.26; 95%CI,1.29-3.97; p=0.019) or GG (OR=1.33; 95%CI, 0.23-7.81; p=0.019) in the codominant model; ii) genotypes GTand GG (OR=2.18; 95%CI, 1.26-3.78; p=0.0061) in the dominant model; iii) GT (OR=2.24; 95%CI, 1.28-3.92;p=0.0053) in the overdominant model; iv) the allele G of rs891835 (OR=1.85; 95%CI, 1.14-3.00; p=0.015) inthe additive model. In addition, “CG” and “CGGAG” were found by haplotype analysis to be associated withincreased GBM risk. In contrast, genotype GG of CCDC26 rs6470745 was associated with decreased GBM risk(OR=0.34; 95%CI, 0.12-1.01; p=0.029) in the recessive model.
Conclusions: Our results, combined with thosefrom previous studies, suggest a potential genetic contribution of CCDC26 to GBM progression among HanChinese.