ROC analysis revealed that galectin-3 had an excellent diagnostic power in RA and SSc and very good diagnostic power for SLE, because the area under curves (AUCs) were as follows in decreasing order: for RA—0.911, for SSc—0.903, and for SLE—0.859 (Figure 2). This evidence concerns the gene LGALS3 and systemic lupus erythematosus.