Bi-allelic variants in FSD1L cause a neurodevelopmental disorder overlapping with L1 syndrome

This study associates bi-allelic variants in FSD1L with a neurodevelopmental disorder closely resembling L1 syndrome, mainly characterized by hydrocephalus and corpus callosum defects. Functional experiments demonstrate that FSD1L encodes a microtubule-associated protein implicated in neuronal differentiation, cell division, cilia formation, axon guidance, and fasciculation.