UBA1 and ichthyosis prematurity syndrome: These findings not only suggest that targeted therapies against UBA1-mutant clones, such as Janus kinase pathway inhibitors or hypomethylating agents, could offer clinical benefit in managing post-transplant complications but also raise the possibility that idiopathic pneumonia syndromes, the causes of death in two cases, may be attributed to persistent UBA1-mutant clones in the lung tissue, although autopsies were not performed in these patients.