HAP1 and neoplasm: The number of stalled forks (# stalled/(# stalled +#restarted) or newly initiated origins ((# CldU/(# stalled +# restarted +#new) is obtained in the following panels. (B) HAP-1 p53 null cells (C) primary MEF with GOF p53 R172P (apoptosis deficient, mildly tumor prone) and p53 R172H (apoptosis deficient, strongly tumor prone), (D, E) primary MEF with p53 S47 (apoptosis and greatly transcription proficient) and null for p53 (for better comparison WT p53 of (C) is re-plotted, shady blue), and (F) human H1299 cells with inducible p53 WT or S47.