For example, in the case of Allergic bronchopulmonary aspergillosis (ABPA), which is unleashed by a Th2 response, an association has been demonstrated with dysfunctions of the cystic fibrosis transmembrane conductance regulator [55], while variations in the prevalence of polymorphisms may explain the differences in the prevalence of ABPA from one geographical area to another. The gene discussed is CFTR; the disease is allergic bronchopulmonary aspergillosis.