Although the five Dutch SFTPC cases had UIP histology, their HRCT scans were not typical of IPF, with features that included diffuse lung involvement, extensive ground glass and multiple cysts In contrast, our 28 familial probands, who all screened negative for SFTPC mutations, had HRCT scans which were classified by our blinded radiology panel as “definitely” or “probably” affected with IPF. This evidence concerns the gene SFTPC and idiopathic pulmonary fibrosis.