The additional value of several clinical attributes was tested, using the low-density array data obtained from untreated patients with a known diagnosis: presence of psoriasis, presence of rheumatoid factors, presence of anti-CCP antibodies, elevated serum CRP values, presence of arthritis in the hands, morning stiffness above 1 hour, number of joints with arthritis, presence of rheumatoid nodules, symmetrical arthritis, X-ray erosions and synovial fluid WBC count. The gene discussed is CRP; the disease is psoriasis.