Whereas in most cases patterns of marker aberrancy were preserved with the adjacent endometriosis (see next paragraph), in this case, the adjacent endometriotic epithelium was nonaberrant for β-catenin, suggesting that a CTNNB1 mutation might have been the instigating molecular driver event within the endometriosis driving the formation of the EBT. The gene discussed is CTNNB1; the disease is endometriosis.