Confirming our previously published results [15], patients with SLE showed detectable serum levels of anti-ERα Abs (Fig. 3b) and a significant difference in the presence of these antibodies between patients with SLEDAI-2K scores <6 and ≥6 was observed (p = 0.0002, Fig. 3b). This evidence concerns the gene ESR1 and systemic lupus erythematosus.