The results showed that the telomere length of the two affected patients (II-1 and II-3) was shorter than that of healthy controls and one of the relatives without the CTC1 variant (II-5) (Fig. 2D), which indicated that mutations in CTC1, a telomere biology-related gene [14], may reduce the length of telomeres and lead to IPF and related diseases. This evidence concerns the gene CTC1 and idiopathic pulmonary fibrosis.