Finally, rs35705950 located in the promoter region of MUC5B was confirmed to be the most strongly associated with familial lung stromal disease and IPF, present in 34% of familial lung stromal disease, 38% of IPF, and only 9% of normal controls, and was considered a risk allele for both diseases 117. Here, MUC5B is linked to idiopathic interstitial pneumonia.