In our binary multiparametric logistic regression model, using high-positive (≥3 × ULN) RF and anti-CCP levels, an acceptable level of differential diagnostic accuracy was achieved, where kidney involvement and anti-Ro/SS-A positivity further increased the chance of having SS-RA, and, on the contrary, anti-La/SS-B positivity decreased it. The gene discussed is SSB; the disease is rheumatoid arthritis.