TREX1 and systemic lupus erythematosus: Defects in DNA damage repair (e.g., TREX1, DNase I), apoptosis (e.g., FASLG), and survival (e.g., PRKCD) of B lymphocytes, and clearance of self-antigen (DNASE1L3) are also implicated in loss of tolerance underlying the onset of monogenic SLE.