WFS1 and Leber hereditary optic neuropathy: As the zebrafish eye is comparable to the human eye27,28, and optic atrophy is a defining clinical feature of WS29, we investigated the morphological and functional characteristics in embryos and adult fish established from two mutant lines carrying stop codon mutations in wfs1a and wfs1b, which are the orthologues of WFS1 in zebrafish.