We then generated five groups of experimental animals: a MathCreERT2-driver/reporter-only group (hereafter referred to as: CreNegative (white)); a Mad2l1-only, and a Trp53-only deletion group (referred to as Mad2f/f (pink), or p53f/f (green)); and two compound deletion mutant groups that were expected to exhibit mild and severe CIN, respectively (Mad2+/f; p53f/f (yellow); and Mad2f/f; p53f/f (blue)) (Figure 4A). The gene discussed is MAD2L1; the disease is cervical squamous intraepithelial neoplasia.