This is because multiple conditions, gynecological (for instance, adenomyosis [26,27,28,29], pelvic inflammatory disease (PID) [30,31,32], uterine fibroids [32,33,34], and ovarian cysts [32,35]) and non-gynecological (for instance, inflammatory bowel disease (IBD) [36], rheumatoid arthritis [37,38,39], asthma [40], anxiety and depression [41,42,43]) could affect the levels of CA125 and BDNF. The gene discussed is BDNF; the disease is pelvic inflammatory disease.