CTLA4 and autoimmune lymphoproliferative syndrome: Recent whole exome sequencing and whole genome sequencing have revealed new potential genetic drivers in the subgroup of ALPS with undetermined genetic defects (ALPS-U).Table 1 lists a number of candidate genes—includingKRAS,NRAS,CTLA4,LRBA,PI3kinase (PI3κ),MAGT1,STAT3, andTNFAIP3 (TNF-α–induced protein 3)—that have all been linked with ALPS-like features26–32.