Perforin Deficiency

**Semantic type:** Disease or Syndrome

**Definition:** A condition of decreased or absent presence of perforin. Deficiency of this protein is associated with T-cell lymphoblastic lymphoma, aplastic anemia, hemophagocytic lymphohistiocytosis familial type 2, autoimmune lymphoproliferative syndrome and other lymphoproliferative disorders, including various forms of lymphoma.