At 4 weeks, back skin of Lgr5 KI/R26R-tdTomato/Ctnnb1lox(ex3)/+ mutant mice showed comprehensive dermal ECM remodeling and CD44 expression in the lower dermis surrounding the pilomatricomas, while the upper dermis contained only mature collagen (Figures 6B and S5D). Here, LGR5 is linked to pilomatrixoma.