Using the unpaired t-test (2-tailed) method to evaluate the difference between the HC and patient sera groups, the differences as follow: each comparison were HC versus JIA IgA: P = 4.4exp−4; IgG: P = 3.43exp−12, for HC versus CD P = 0.004; P = 1.28exp−14, for HC versus CrD P = 2.81exp−8; P = 6.7exp−16, for HC versus HPF P = 0.01; P = 8.43exp−6, for HC versus PFAPA P = 0.02; P = 0.05 (Table 2). The gene discussed is CD79A; the disease is juvenile idiopathic arthritis.