TP53 and cancer: The observation that certain genes tend to be mutated in CNA-rich (TP53 and SPOP [Ciriello et al., 2013; Boysen et al., 2015]) or CNA-poor (CTCF and ARID1A [Ciriello et al., 2013]) cancers implies that, besides epigenetic factors, the genetic background of the cell influences CNA variation.