Mutations in TUBB4A have been identified to cause a wide phenotypic spectrum of diseases ranging from hereditary generalized dystonia with whispering dysphonia (DYT-TUBB4A) and hereditary spastic paraplegia (HSP) to leukodystrophy hypomyelination with atrophy of the basal ganglia and cerebellum (H-ABC).
Dystonia-4 (DYT4) is another autosomal dominant dystonia that is characterized by onset in the second to third decade of progressive laryngeal dysphonia.
Mutations in TUBB4A have been identified to cause a wide phenotypic spectrum ranging from hereditary generalized dystonia with whispering dysphonia (DYT4) to the leukodystrophy hypomyelination syndrome with atrophy of the basal ganglia and cerebellum (H-ABC).
Mutations in the TUBB4A gene have been identified so far in two neurodegenerative disorders with extremely different clinical features and course: whispering dysphonia, also known as dystonia type 4 (DYT4), and hypomyelination with atrophy of the basal ganglia and cerebellum (H-ABC).