Type 6 hypomyelinating leukodystrophy caused by a de novo mutation in the tubulin beta-4A gene

The article presents the results of long-term dynamics of the clinical and radiological picture of a child with a rare neurodegenerative disease — hypomyelinating leukodystrophy, type 6 (hypomyelinating leukodystrophy with atrophy of the basal ganglia and cerebellum) caused by a de novo mutation in the TUBB4A gene. The TUBB4A gene encodes a brain-specific protein — tubulin beta-4A, being a part of the walls of microtubules, which are the main component of the cytoskeleton. Mutations of the TUBB4A gene decrease the stability of microtubules, violate their functions of maintaining the cellular structure and transportation. Hypomyelinizing leukodystrophy, type 6, is manifested by a delayed motor development, instability of the gait with an increase in extrapyramidal disorders in young children. The authors substantiate the need for a multidisciplinary approach to the diagnosis and management of patients of this category and emphasize that the modern molecular genetic methods, in particular sequencing of a new generation are the key methods in the diagnosis of hypomyelinizing leukodystrophies.

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