Hypomyelination with atrophy of the basal ganglia and cerebellum (H-ABC)



Autosomal dominant or sporadic

Inheritance from one parent will result in the disease

Age range at onset:

Infancy or early childhood

Specialists you may see:


Severity and progression of symptoms can vary, and may include learning difficulties, delayed motor development, spasticity, dystonia and hyperreflexia. Speech and swallowing problems may also develop, and it is also possible for those with H-ABC to develop hearing problems and nystagmus.


Caused by mutations in the TUBB4A gene. This can be inherited but typically is the result of a sporadic mutation.

The TUBB4A gene is involved in forming microtubules, which give cells their shape. The gene is found most commonly in the central nervous system. When the gene is mutated, the formation and stability of microtubules is compromised, impairing the structure or function of cells in the central nervous system and causing the symptoms described.