ARL3 and Joubert syndrome: Recently, human mutations in Arl3 have been linked to various forms of retinal degeneration: R99I causes autosomal recessive cone-rod dystrophy (Sheikh et al., 2019), R149H or R149C cause recessive Joubert syndrome (Alkanderi et al., 2018), compound heterozygous T31A/C118F causes rod-cone dystrophy (Fu et al., 2021), Y90C causes autosomal dominant retinitis pigmentosa (Holtan et al., 2019; Strom et al., 2016), and D67V causes autosomal dominant retinal degeneration (Ratnapriya et al., 2021).