Serological biomarkers are commonly used in immunosensors, ELISAs, and PCR, with key breast and gynecological cancer biomarkers including breast cancer associated gene 1 and 2 (BRCA1 and BRCA2), cancer antigen-125 (CA-125), human epididymis protein 4 (HE-4), mesothelin alpha fetoprotein, osteopontin, human epidermal growth factor receptor 2 (HER2), and human papillomavirus (HPV) virus. The gene discussed is ERBB2; the disease is female reproductive organ cancer.