In the anti-cN-1A-positive patients, a higher rate of autoimmune co-morbidity was seen: 15% of the anti-cN-1A-positive pSS and 50% of the anti-cN-1A-positive SLE patients suffered from one or more other autoimmune diseases, whereas autoimmune comorbidity was observed in 5 and 30%, respectively, of the anti-cN-1A-negative patients (p = 0.05 in pSS, p = 0.02 in SLE). The gene discussed is NT5C1A; the disease is autoimmune disease.