In 2023, preclinical studies conducted by McAuley and colleagues [111] toward curing CD3δ severe combined immunodeficiency showed that adenine base editing of HSPCs effectively converted the disease’s pathogenic point mutation c.202C>T in CD3D in a cell line-based study and lentivirus-induced pathogenic mutations in healthy human CD34+ cells’ disease models, and in CD34+ HSPCs from a patient with the disease [111]. The gene discussed is CD3D; the disease is Immunodeficiency.