An X-linked neurodegenerative disorder characterized by intellectual deficit, blindness, convulsions, spasticity, mild hypomyelination and early death. It has been described in about ten male members from two generations of one family. The genetic defect responsible for the disorder is located in the pericentromeric region of the X chromosome, Xp11.3-q12. The disease is X-linked neurodegenerative syndrome, Hamel type (MONDO_0019429).