Introduction
STAT1 [signal transducer and activator of transcription-1] is a critical transcription factor mediating interferon signaling (1).STAT1 gene defects progress with infection susceptibility, chronic diarrhea, and recurrent skin infections. The genetic dissection of various human infectious diseases has led to the definition of inborn errors of human STAT1 immunity of four types, including autosomal recessive (AR) complete STAT1 deficiency, AR partial STAT1 deficiency, autosomal dominant (AD) STAT1 deficiency, and AD gain of STAT1 activity (1). Heterozygous STAT1 gain-of-function (GOF) mutations cause autosomal dominant chronic mucocutaneous candidiasis (CMC), but have also been associated with a much broader spectrum of infectious, inflammatory, vascular, and neoplastic manifestations (2). These experiments of nature neatly highlight the clinical and immunological impact of the human genetic dissection of infectious phenotypes (1).