LIG4 and immune system disorder: Patients with combined immunodeficiencies due to radiosensitive disorders such as DNA ligase 4 deficiency, Cernunnos-XLF deficiency or Nijmegen breakage syndrome may be detected by newborn screening for SCID, or present with immunodeficiency, autoimmunity, myelodysplasia or malignancy, particularly leukemia or lymphoma, and may require transplantation [41].