IFNA1 and systemic lupus erythematosus: A role for interferon (IFN) in the pathogenesis of systemic lupus erythematosus (SLE) has been proposed since early experiments showed elevated IFN activity in SLE patients1,2 and the advent of gene expression profiling demonstrated a robust IFN gene signature (IGS) in SLE patient peripheral blood, purified B cells, T cells, monocytes, and affected organs3–7.