CHRNB1 and glioblastoma: We first queried the dataset to determine the frequency of mutations in the muscarinic AChR (mAChR) genes: CHRM1-5; neuronal nicotinic AChR (nAChR) genes: CHRNA2-7, CHRNA9-10, and CHRNB1-4; and muscle nAChR genes: CHRNA1, CHRNB1, CHRND, CHRNE, and CHRNG. Genomic mutations in these genes were found to be rare, occurring in ≤1% of all GBM samples (Table S1).