TP53 and Leber congenital amaurosis: Accordingly, MBs are now classified into the following four categories that are associated with peculiar prognostic features: WNT-activated with classic or LCA (very rare) histology; SHH-activated (wild-type TP53) with classic, D/N, or LCA histology; SHH-activated (mutant TP53) with classic, LCA or D/N (very rare) histology; non-WNT/non-SHH group with classic or LCA histology (Group 3 and Group 4) [12,13].