C2 and systemic lupus erythematosus: Screening through 117 cSLE patients fulfilling the ACR criteria for SLE, Belot et al. reported that the mendelian genotypes involving variants in C1QA, C1QC, C2, DNASE1L3, and IKZF1 were confirmed in 8 patients, while 7 additional cases harbored heterozygous variants in complement or type I interferon-associated autosomal recessive genes.