In contrast to their study, we used only mid-to-late proliferative samples with clearly determined stages of EM disease, where we were able to detect changes in protein expression showing a stage-dependent reduction of FN1 expression, suggesting that not only the receptors are regulated in endometrium of women with EM, but also the FN1 protein itself plays a role in endometriosis. The gene discussed is FN1; the disease is endometriosis.