TP53 and cervical squamous intraepithelial neoplasia: In the first instance, we set out to model the HRD CIN class, using CRISPR/Cas9-mediated gene editing to first mutate TP53 then BRCA1, followed by overexpression of MYC. A panel of derivative subclones was subjected to functional assays, karyotyping and transcriptional profiling to determine (1) whether CIN had been induced and (2) what the potential mechanisms might be.