RB1 and neoplasm: Comparing homozygous deletion rates at a set of known tumour suppressors (see further) in diploid and tetraploid tumours, no differences were detected, except at the RB1 locus, which was ~7× more frequently lost in tetraploid tumours (p = 1.01 × 10−3; Fisher–Boschloo’s exact unconditional test; Supplementary Fig. 2e).