The importance of considering monogenic causes of autoimmunity: A somatic mutation in KRAS causing pediatric Rosai-Dorfman syndrome and systemic lupus erythematosus.

Objectives: Clinicians need to be aware of the growing list of defined monogenic etiologies of autoimmune diseases. This is particularly relevant when evaluating children, as these rare monogenic forms of autoimmunity tend to present very early in life.

Methods And Results: By harnessing the transformative power of next generation sequencing, we made the unifying diagnosis of RAS-associated autoimmune leukoproliferative disease (RALD), caused by the somatic gain-of-function p.