RPGRIP1L and Bardet-Biedl syndrome 13: Within our candidate gene list are seven genes related to cilia function, Mks1, B9d2, Rpgrip1l, Cc2d2a, Ehd1, Sh3pxd2a, and Ezr. MKS1 is a component of the primary cilia and is mutated in Meckel syndrome type 1 and Bardet-Biedl syndrome type 13.