Copy number variations dominated changes in cancer-related genes in DCKO mice, with typical high-level amplifications observed for oncogenic drivers, e.g., Myc, Ccnd1, and Cdks, as well as gastrointestinal transcription factors, e.g., Gata4, Foxa1, and Sox9. Interestingly, frequent alterations in gastrointestinal transcription factors in DCKO mice indicated their potential role in tumorigenesis. Here, CCND1 is linked to cancer.