Another distinct entity from EM is Rowell syndrome (RS), a clinical triad of EM-like lesions, lupus erythematosus, and particular immunologic patterns such as speckled pattern of antinuclear antibody (ANA), positive anti-Ro/SSA or anti-La/SSB, and positive rheumatoid factor (RF), all of which are required to meet the diagnostic criteria for RS. This evidence concerns the gene BTG3 and X-linked retinoschisis.