No association of (-131C→G) variant of CHI3L1 gene with risk of glioblastoma and prognosis

Expression of CHI3L1 (YKL-40) has been correlated with prognosis of glioblastoma. The variant allele (-131C -> G) of CHI3L1 promoter results in a lower transcription of CHI3L1. Therefore, we tested the hypothesis that the G variant could protect against the risk of gliomas or have a favorable prognostic impact. DNA from 296 glioblastoma patients and 190 controls were genotyped on the -131 allele. Tumor RNA was obtained from 108 patients for CHI3L1 transcript quantification. Neither genotype nor allele distribution differed between patients and controls. There was no significant difference in survival between the CC, CG, and GG patients despite the few GG patients tended to have a longer survival. There was no correlation between genotype and CHI3L1 expression in tumor samples. Taken together our data suggest that the variant allele (-131C -> G) of CHI3L1 promoter has no significant impact on survival and is not a prognostic factor for glioblastoma.