TREX1 and systemic lupus erythematosus: The exonuclease, three prime repair exonuclease 1 (TREX1), degrades cytosolic DNA (Mazur and Perrino, 1999; Crow et al., 2006) and its deficiency leads to multiple inflammatory and autoimmune diseases such as systemic lupus erythematosus, Aicardi–Goutieres syndrome, and familial chilblain lupus (Rice et al., 2015).