TUBB4B and sensorineural hearing loss disorder: From all this, we firstly conclude that patients with amino acid substitutions at position 391 of the TUBB4B protein exhibit a distinct retinal phenotype with round yellowish peripheral lesions with pigmented spots, corresponding to LCA and SNHL, and secondly, that patients with mosaicism at this position show a sectorial pattern with the presence of bone spicules and a milder disease course.