Exemplary gene sequences that cluster with PRKR and OAS3. Hierarchical clustering was performed on the total study population to determine genes that cluster with PRKR and OAS3. A visual demonstration of the expression of a selection from those genes, comprising a partial IFN signature, is shown. Data are shown from a subset of SLE samples tested (n = 14) and from rheumatoid arthritis (RA) (n = 11), juvenile chronic arthritis (JCA) (n = 2), and control samples (n = 8). Relative expression compared with an internal control ranged from approximately -0.5 (bright green) to 0.5 (bright red).