► TMEM114 and TMEM235 are phylogenetically distinct from claudins. ► In polarised cells Tmem114 and Tmem235 have a different localisation to claudins. ► Tmem114 and Tmem235 are N-glycosylated. ► TMEM114 and TMEM235 are expressed in the developing human eye and CNS. ► Knockdown of Tmem114 in Xenopus causes microphthalmia. A novel gene, TMEM114, was annotated as a member of the claudin gene family and was subsequently associated as a cause of autosomal dominant cataract because of a translocation in its putative promoter. Our bioinformatic and molecular analyses of TMEM114, and the closely related TMEM235, demonstrate that these proteins are more closely related to members of the voltage dependent calcium channel gamma subunit family. TMEM114 and TMEM235 differed from claudins in terms of localisation in polarised epithelial cells and by the presence of N-linked glycans. By gene expression knockdown in Xenopus tropicalis we also demonstrate a role for Tmem114 in eye development. Claudin-2 and ZO-1colocalize by fluorescence microscopy (View interaction). ZO-1 and Tmem114colocalize by fluorescence microscopy (View interaction).