Other avenues of research that may yield opportunities for therapeutic intervention include the study of various STAT mutations, such as STAT1 mutations associated with impairments in IL-17 immunity, and linked with chronic mucocutaneous candidiasis, and STAT3 gain-of-function mutations that are linked with altered T cell and cytokine signalling and with lymphoproliferation and autoimmunity with prominent cytopenias. The gene discussed is IL17A; the disease is chronic mucocutaneous candidiasis.