MUC5B and idiopathic interstitial pneumonia: Studies have uncovered some rare genetic variants such as TERT (telomerase reverse transcriptase) [9, 10], TERC (telomerase RNA component) [10], and some common gene polymorphisms such as MUC5B (mucin 5B, rs35705950) [11] are associated with the development of sporadic IPF or familial interstitial pneumonia (FIP).