BICC1 and cyst: With proper consideration of the differences between flies and humans and of the hierarchical relationship between the BicC and PKD1 genes, the BicC cystic fly may offer opportunity to chart conserved pathways that are altered in BicC mutation, are relevant for cyst formation and/or progression, may allow to form new hypotheses on BicC function and disease mechanism, and contribute to our understanding of the larger functional context of human PKD.