Recent study showed that SASH3 is important for T-cell proliferation, activation and cell survival, and lack or mutation of SASH3 could lead to a new type disease of human X-linked combined immunodeficiency, which was manifested as CD4+ T-cell lymphopenia, decreased T-cell proliferation, cell cycle progression, and increased T-cell apoptosis in response to mitogens (43). The gene discussed is CD4; the disease is combined immunodeficiency, X-linked.