CCDC8 and 3M syndrome: Consistent with the role of CUL7, OBSL1 and CCDC8 as growth-promoting genes, and their association with cell cycle proteins, we have previously shown that fibroblast cells from 3-M syndrome patients with null mutations in the 3-M genes have a significantly reduced level of cell proliferation compared with normal control fibroblast cells (Murray et al. 2013).