KRAS and Patent ductus arteriosus: Genetically engineered mouse models (GEMMs) that harbor pancreas-specific expression of oncogenic Kras, such as KC (LSL-KrasG12D; p48/Pdx-1-Cre) (26) and iKras* model (p48-Cre; R26-rtTa-IRES-EGFP; TetO-KrasG12D) (27), recapitulate the stepwise carcinogenesis process of human PDA.