To adapt the alphoidtetO-HAC [16] for CIN studies, the tDNA-shEGFP-mCherry plasmid (A245) (Supplementary Figure S2) was inserted into a single loxP loading site of the HAC [22] in HPRT-deficient Chinese hamster ovary (CHO) cells (Figure 2A). The gene discussed is HPRT1; the disease is cervical squamous intraepithelial neoplasia.