NOTCH1 and neoplasm: Mutations in both domains were not mutually exclusive (P = 0.59, Fisher’s Exact), but mutations in the PEST domain of Notch1 were highly associated with tumours positive for the type 1 deletion (P < 0.0001, Fisher’s Exact); while conversely, mutations in the HD domain were highly associated with type 1 deletion-negative tumours (P < 0.003, Fisher’s Exact).