In this study, we used a SmD1 polypeptide-based ELISA to determine anti-SmD1 antibody in 269 SLE, including100 naïve (had not been treated with steroids or immunosuppressants at study inception) SLE patients and 169 non-naive SLE patients; 233 controls with other rheumatic diseases (RDC) (70 RA, 40 AS, 73SSc, and 50 SS), and 110 healthy controls (HC) group. This evidence concerns the gene SNRPD1 and rheumatoid arthritis.