Next, we identified five key genes associated with the TGF-β pathway in endometriosis: NBL1, EMP3, ID2, DCN, and THBS1. Although all these genes may be identified as potential biomarkers in endometriosis progression, we prioritized THBS1 for further analysis due to prior evidence and its comparative status among key biomarkers. Here, ID2 is linked to endometriosis.