However, despite initial responses to trastuzumab or trastuzumab conjugate regimens, approximately 70% of HER2-positivie breast cancer patients develop resistance within the first year of treatment (Kreutzfeldt et al., 2020; Wang et al., 2022; Vivekanandhan and Knutson, 2022). The gene discussed is ERBB2; the disease is breast carcinoma.