Genetic alterations in splicing process in KrasG12D/+ cells may contribute to the observed transcriptional heterogeneity in the expression of cancer‐associated MUC4.[10, 12] Although the precise mechanism remains to be explored, the mutations in Muc4 may trigger alternative splicing of Muc4, resulting in an increase in Muc4/X and Muc4/Y for PanIN initiation. This evidence concerns the gene MUC4 and cancer.