Interestingly, no significant difference on the correlation of anti-GP2 IgG with disease location was observed in Czech Republic CD patients.29 Bogdanos et al revealed the association between anti-GP2 IgG with structuring behavior (B2) and perianal disease in CD patients.17 However, no significant difference of anti-GP2 IgG with structuring behavior (B2) and perianal disease was observed in our study with Chinese CD patients. The gene discussed is GP2; the disease is Cowden disease.