An autoimmune lymphoproliferative syndromes (ALPS) screening panel was positive with a score of 4/4, and follow-up sequencing on the ALPS gene panel (including the genes CASP8, CASP10, FADD, FAS, FASLG, ITK, KRAS, MAGT1, NRAS) was conducted and detected a variant of uncertain significance (VUS) in FAS: c.710C > T (p.A237V). Here, FADD is linked to autoimmune lymphoproliferative syndrome.