Importantly, we found that the levels of fecal IgA and IgG were positively correlated with CRP, ESR, CDAI, SES-CD, Mayo scores and UCEIS of patients with CD or UC, respectively, suggesting that fecal IgA and IgG may serve as an important parameter for monitoring the disease activity in IBD patients. The gene discussed is CD79A; the disease is inflammatory bowel disease.