Idiopathic pulmonary fibrosis (IPF) is the most common type of interstitial lung disease. "Idiopathic" means the underlying cause of the condition is not known.
But genetics appear to play a role in the development of IPF. About 30% of the risk of developing IPF is related to a gene called MUC5B.
Other causes of interstitial lung disease include certain autoimmune conditions and dust, mold, or irritants in your environment.