We obtained MMRD-associated genes from cBioportal, namely, CHEK1, CHEK2, RAD51, BRACA1, BRACA2, MLH1, MSH2, ATM, ATR, MDC1, PARP1, and FANCF. Among them, MSH2 defects were found in 0.2% of the GBMs and 0.6% of all primary brain tumors in TCGA data. This evidence concerns the gene MDC1 and brain neoplasm.