However, both LBR and Tm7sf2 have 3beta-hydroxysterol Delta(14)-reductase activity (Silve et al., 1998; Bennati et al., 2006), and this activity was suggested to be important for the pathophysiology of Greenberg skeletal dysplasia caused by LBR mutations (Waterham et al., 2003). Here, LBR is linked to skeletal dysplasia.