Autosomal dominant hyper-IgE syndrome, STAT-1 mutations, auto-immune poly endocrine syndrome type 1, hyper-IgM syndrome, chronic mucocutaneous candidiasis, deficiencies in IL-17R, IL-17F, IFN-γ and IL-12, DiGeorge syndrome, Ataxia telangiectasia, Wiskott-Aldrich syndrome, X-linked lymphoproliferative syndrome, MHC deficiency, and Cartilage-hair hypoplasia. Here, STAT1 is linked to X-linked lymphoproliferative disease.