Abnormal type I collagen (α1)3 homotrimer, derived from COL1A1 alone, is genetically or biochemically associated with common age-related human diseases including osteoporosis (Ralston et al., 2006), osteoarthritis (Bailey et al., 2002; Kerns et al., 2014; Philp et al., 2017), intervertebral disc degeneration (Zhong et al., 2017), arterial stiffening (Brull et al., 2001), cancer (Makareeva et al., 2010), liver fibrosis (Rojkind et al., 1979) and Dupuytren's contracture (Ehrlich et al., 1982). The gene discussed is COL1A1; the disease is osteoporosis.