Mutations in human CUL4B cause intellectual disability (Tarpey et al., 2007; Zou et al., 2007) and patients with CUL4B mutations manifest disruptions in skeletal development such as a short stature and brachydactyly (Badura-Stronka et al., 2010; Isidor et al., 2010; Kerzendorfer et al., 2011; Ravn et al., 2012). Here, CUL4B is linked to Intellectual disability.