TREX1 and systemic lupus erythematosus: Variants in TREX1 cause various syndromes including those associated with excessive type I interferon signaling include autosomal-recessive (AR) Aicardi-Goutières syndrome; autosomal-dominant (AD) AGS; AD familial chilblain lupus (FCL); and AD systemic lupus erythematosus (SLE) (9).