Moreover, collagen XII deficiency has also been shown to contribute to UCMD- and BM-like phenotypes, as demonstrated by genetic deletion of Col12a1 in mice, which results in muscular dystrophy, decreased grip strength (Zou et al. 2014), and connective tissue defects, such as kyphosis and decreased bone mass (Izu et al. 2011b). Here, COL12A1 is linked to Ullrich congenital muscular dystrophy.