ABSTRACT
Overall, there is compelling circumstantial evidence for a genetic predisposition to develop IPF and other forms of pulmonary fibrosis. This is supported by clear evidence of IPF and other fibrotic lung diseases in families through several generations and identification of specific genetic abnormalities in small groups of patients. Efforts to identify specific genetic factors that relate to larger populations of patients have been hampered by the low incidence of disease and by the high degree of overlap of various types of pulmonary fibrosis. Future progress to define genetic abnormalities that relate to IPF and other fibrotic lung disease will require consistent and precise application of case definition and inclusion criteria. It is unlikely that a single genotype will be identified which leads to the development of IPF. Rather, it is more plausible that multiple genes with different levels of penetrance or expression, as well as multiple environmental triggering factors combine to produce the disease. Thus, a clear link of the genetic component for most patients with IPF will depend upon simultaneous recognition and careful control of environmental and other nongenetic factors.
