TMEM67 and Joubert syndrome: Dvl is essential for this process of basal body docking, ciliogenesis and PCP (Wallingford et al., 2000; Park et al., 2008) as are transition zone proteins meckelin (TMEM67) and TMEM216, and basal body protein MKS1 (Figure 4), which are mutated in Joubert syndrome and Meckel-Gruber syndrome, the most severe ciliopathies (Dawe et al., 2007, 2009; Valente et al., 2010; Adams et al., 2012; Figure 7, Table 1).