The genes relevant to familial HLH (FHLH) including PRF1, UNC13D, STX11, STXBP2 [3], were analyzed to confirm the mutations, as well the genes related to immune deficiency syndromes associated with HLH: XIAP and SH2D1A [3, 13]. The gene discussed is STXBP2; the disease is hemophagocytic syndrome.