Many signals are consistent between autoantibody development and SLE risk (e. g. HLA-DRB1*09:01 and DRB1-11Asp, shared between SLE, nRNP+ and ACL+ risk; HLA-DRB1*13:02 and DRB1-13Ser, strongly protective for both SLE and nRNP+). This evidence concerns the gene HLA-DRB1 and systemic lupus erythematosus.