Consistently, it has been found that IL-6, IL-10, IL-13, interferon (IFN)-γ, and monokine induced by IFN-γ (MIG; CXCL9) express at significantly higher levels in the cerebrospinal fluid of the PE patients than in those with isolated BE [14]–[16]. The gene discussed is CXCL9; the disease is Barrett esophagus.