LAMB3 and junctional epidermolysis bullosa: JEB is caused by defects in laminin 332, integrin α6β4, or type XVII collagen that are caused by pathogenic variants in the LAMA3 (Laminin α3 chain, OMIM 600805), LAMB3 (Laminin β3 chain, OMIM 150310), LAMC2 (Laminin γ2 chain, OMIM 150292), ITGA6 (Integrin α6, OMIM 226730), ITGB4 (Integrin β4, OMIM 147557), or COL17A1 (Type XVII Collagen, OMIM 113811) genes.