Few examples of CDx assays are the THXID BRAF Kit which qualitatively detects the presence of BRAF mutations in patients with metastatic melanoma by polymerase chain reaction (PCR) (https://www.biomerieux-diagnostics.com/thxidr-braf), Herceptin, HER2 PharmDx Kit based on immunohistochemistry (IHC) and fluorescence in situ hybridization (FISH) platforms, which determine the overexpression of the HER2 protein and gene in patients with breast cancer (42). The gene discussed is ERBB2; the disease is breast cancer.