TYRP1 and melanoma: We observed a significantly higher number of cells positive for TYRP1 in the trigenic group compared to the bigenic group with spontaneous melanomas (Fig. 4e), and a significant increase in TYRP1+ cells in LNs from the Rxrαep−/− mice compared to their RxrαL2/L2 controls post acute neonatal UVB exposure (Fig. 4f).