In a genome-wide linkage scan and subsequent fine mapping of a risk locus on 11p15.5, the minor allele of a common variant (rs35705950) within MUC5B has been found to be present in 34% of FPF cases, 38% of IPF cases and 9% of controls [22]. This evidence concerns the gene MUC5B and idiopathic pulmonary fibrosis.