The many faces of KIF7.

Mutations in KIF7, the gene that encodes a component of the kinesincomplex of anterograde intraflagellar transportin the cilia, have been reported to cause a range of phenotypesincluding hydrolethalis, acrocallosal syndromeand Joubert syndrome. In a cohort of patients with various neurogenetic phenotypes, we identified novel KIF7 mutations in two families that span the known phenotypicspectrum of KIF7- related disorders. Surprisingly, we also identified a novel truncating KIF7 mutation in a third consanguineousfamily, in which the index presented with intellectual disabilitybut no overt signs of ciliopathy, and his brain magnetic resonance imaging revealed an isolated dysgenesisof corpus callosum. This small cohort contributes novel pathogenic alleles of KIF7 and suggests that KIF7-related phenotypescan include isolated dysgenesisof corpus callosumwith intellectual disability, thus expanding the range of phenotypesthat warrant sequencing of this gene.