Allopolyploids are formed by interspecific hybridization and whole genome duplication, with the resulting organism contains multiple distinct subgenomes in one nucleus. Subgenomic interactions result in massive genetic and epigenetic reconstruction, contributing to variable phenotypic traits noted in newly formed allopolyploids. To better understand these mechanisms in the context of molecular biology, evolution, and plant breeding, plant biologists study the model organism Brassica napus (farmed as canola or oilseed rape). With white-flowering and yellow-flowering progenitors, flower color phenotype of B. napus presents an opportunity to examine subgenomic interactions. CAROTENOID CLEAVAGE DIOXYGENASE 4 (CCD4) is known to play a major role in determining flower color phenotype of carotenoid-synthesizing angiosperms. Here, we investigate the genetic and epigenetic role of CCD4 orthologs and their role in flower color phenotype of B. napus.