variants dysregulate splicing and cause hypomyelinating leukodystrophy.

Objective: To further clarify the molecular pathogenesis of RNA polymerase III (Pol III)-related leukodystrophy caused by biallelic variants at a cellular level and potential effects on its downstream genes.

Methods: Exome analysis and molecular functional studies using cell expression and long-read sequencing analyses were performed on 1 family with hypomyelinating leukodystrophy showing no clinical and MRI findings characteristic of Pol III-related leukodystrophy other than hypomyelination.

Results: Biallelic novel alterations, c.