KRTDAP and keratoconus: Pairwise differentially expressed gene analysis demonstrated that although the transition KC population has higher differentiation marker expression of KRT1 and KRTDAP than basal cells, the differentiated KC population has much higher KRT1, KRT10, and KRTDAP than transition KC, along with additional well-studied terminal differentiation markers LOR, KRT2, and DSC1 [33] (Fig. 5e).