IRF8 and systemic lupus erythematosus: Two well-known SLE associated loci, IRF8 and TNFSF4, showed evidence of significant association in the opposing effect meta-analysis with some evidence for colocalisation of shared signals at both loci (IRF8 PPH4 = 0.36, TNFSF4 PPH4 = 0.37; Tables C and D and Fig A in S1 Text).