Correlation of GFAP to malignancy grade.Grade I higher levels compared to other grades.Grade II significantly higher compared to grade IV.Within grade II glioma GFAP levels were higher in:IDHmut compared to IDHwtATRX loss compared to ATRX retentionNo significant correlation of GFAP to survival after correction for age and tumor grade. Here, ATRX is linked to glioma.