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GTR Home > Conditions/Phenotypes > Leukodystrophy, hypomyelinating, 21

Leukodystrophy, hypomyelinating, 21

Summary

Hypomyelinating leukodystrophy-21 (HLD21) is an autosomal recessive neurodegenerative disorder characterized by global developmental delay apparent from infancy with loss of motor, speech, and cognitive milestones in the first decades of life. Affected individuals show cerebellar and pyramidal signs, including nystagmus, ataxia, dystonia, and spasticity, resulting in the loss of ambulation. Other more variable features include feeding difficulties, poor overall growth with microcephaly, optic atrophy, and seizures. Brain imaging shows diffuse hypomyelination of the white matter and atrophy of the cerebellum and corpus callosum. The disorder is progressive and may lead to premature death (summary by Dorboz et al., 2018). For a general phenotypic description and a discussion of genetic heterogeneity of HLD, see 312080. [from OMIM]

Available tests

2 tests are in the database for this condition.

Clinical tests (2 available)

Molecular Genetics Tests

Genes See tests for all associated and related genes

  • Also known as: C11, C11-RNP3, HLD21, My010, RPC10, RPC11, RPC12.5, POLR3K
    Summary: RNA polymerase III subunit K

Clinical features

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Imported from Human Phenotype Ontology (HPO)

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