One patient with DNA ligase IV-SCID died following TCRαβ-HaploSCT from disseminated adenovirus; one patient with JAK3-SCID died following an MFD transplant due to disseminated CMV with TMA; three patients with Artemis SCID died after one MFD transplant (respiratory failure from RSV pneumonitis) and two MUD transplants (multi-organ failure with influenza A in one, and pulmonary TMA in the other). Here, LIG4 is linked to respiratory failure.