CASP8 and autoimmune lymphoproliferative syndrome: Pathogenic germline variants in other genes affecting the FAS-related apoptosis pathway have been reported as a cause of ALPS in a minor fraction of patients: FASLG (FAS ligand) (10), FADD (FAS-associated death domain protein) (11), CASP8 (caspase 8) (12), and CASP10 (caspase 10) (13).