For example, mutations in the CFTR gene have been shown to be involved in maintaining the balance between Th1 and Th2 responses, with CD4+ T-cells derived from CF patients exhibiting Th2 bias in vitro compared with controls.63A. fumigatus has also been shown to generate extensive lung inflammation and an enhanced Th2-biased immune response in CFTR deficient mice compared with controls.64 The gene discussed is CFTR; the disease is cystic fibrosis.