ARL13B and Joubert syndrome: Common ciliary markers are expressed, such as ADP-ribosylation factor-like protein 13B (ARL13B), inositol polyphosphate-5-phosphatase E (INPP5E) (Fig. 2C) which are associated with Joubert syndrome, as well as centrosome marker pericentrin (PCTN) (Fig. 2D), thus indicating that these cells are an excellent model for investigating ciliary disorders, e.g., Joubert syndrome.