Comparison between participants without endometriosis (n = 5) and participants with endometriosis (n = 4) with high serum JUP values (>220 ng/mL) identified nine DEGs (HBB, HBA1, HBA2, and RGPD2 in CD14+ monocytes; CH25H, HBB, LTB, and KLRC1 in γδt; IFIT2 in NK-CD56bright and JUN in Treg). The gene discussed is HBB; the disease is endometriosis.