In addition, SPP1 may be a useful biomarker for the development and progression of fibrotic lung diseases (Boon et al. 2009; Kadota et al. 2005; Kelly et al. 2006; O’Regan et al. 2006; Pardo et al. 2005; Selman et al. 2006; Vij and Noth 2012). The gene discussed is SPP1; the disease is lung disorder.