Mosaic KRAS variants in childhood-onset systemic lupus erythematosus

Clinical targeted sequencing identified low-VAF KRAS variants in two of 26 children with childhood-onset systemic lupus erythematosus (SLE). Both had severe inflammatory manifestations but lacked Noonan syndrome features, and neither developed persistent lymphoproliferation suggestive of RAS-associated autoimmune lymphoproliferative disease during follow-up. These findings suggest that KRAS mosaicism may contribute to the development or severity of childhood-onset SLE.