White matter disorders have long been associated with the loss, abnormal development or progressive deterioration of myelin, the insulating material that allows nerve cells to communicate rapidly and efficiently. Yet a growing body of research is revealing that many of these conditions may begin much deeper inside the cell, in the molecular systems responsible for reading genes, processing RNA and building proteins. A new review by Chapleau, Villa Tobón and Bernard brings together this expanding group of hereditary diseases, showing how disruptions to the central dogma of molecular biology can produce highly selective and often devastating effects in the brain.
The disorders discussed in the review include leukodystrophies and genetically determined leukoencephalopathies, a broad collection of rare neurological diseases defined by abnormalities in the brain’s white matter. On magnetic resonance imaging, affected tissue may appear unusually bright, damaged or reduced in volume. Clinically, patients can experience developmental delay, movement abnormalities, seizures, cognitive decline, vision problems or progressive loss of motor function. Despite these shared radiological features, the underlying causes are remarkably diverse, ranging from defects in transcription to failures in RNA maturation or protein production.
Transcription is the first step in converting genetic information into biological function. During this process, DNA sequences are copied into messenger RNA, which carries instructions to the cellular machinery that produces proteins. Mutations in genes controlling transcription can alter which genes are switched on or off, when they are activated and how strongly they are expressed. In the developing and mature nervous system, even modest disturbances in this regulatory network can have far-reaching consequences, particularly in cells that must maintain elaborate structures over many decades.
RNA processing introduces another layer of vulnerability. Newly formed RNA molecules must be edited, spliced and transported before they can serve as accurate templates for protein synthesis. Errors in these steps can produce abnormal or incomplete proteins, reduce the availability of essential transcripts or disrupt the balance between different protein variants. Because neurons and glial cells rely on precisely coordinated gene expression, defective RNA processing may interfere with axonal maintenance, cellular energy management, myelin formation or responses to injury.
Translation, the final stage of the pathway, converts RNA instructions into proteins at the ribosome. Pathogenic variants affecting translation factors, ribosomal components or related quality-control systems can impair the production of proteins throughout the cell. The consequences may be especially severe in the central nervous system, where neurons have extraordinary demands for energy and protein renewal, while oligodendrocytes must generate and maintain large quantities of myelin. A disturbance in protein biosynthesis can therefore undermine both the cells that transmit signals and the cells that insulate them.
One of the most intriguing features of these disorders is their selective neurological impact. The molecular machinery affected by many of the mutations is present in nearly every cell, yet the symptoms often center on the brain and spinal cord. The review highlights this unresolved question as a central theme in the field. Several factors may contribute, including the long lifespan of neurons, the complexity of their connections, the dependence of white matter on specialized glial cells and the unusually high metabolic cost of maintaining myelin. Tissue-specific gene regulation and differences in cellular stress responses may also determine why a broadly expressed defect produces a predominantly neurological disease.
The clinical and radiological diversity of these conditions makes diagnosis particularly challenging. Some patients develop symptoms during infancy or childhood, while others remain well until adolescence or adulthood. White matter changes may be widespread, confined to specific regions or accompanied by abnormalities in the cerebellum, brainstem, spinal cord or peripheral nerves. In certain disorders, imaging patterns can offer an important diagnostic clue; in others, the findings overlap with those of unrelated genetic, inflammatory or metabolic diseases. Integrating clinical history, MRI features, biochemical testing and genomic analysis has therefore become essential.
The review also points to a broader shift in how researchers understand hereditary white matter disease. Rather than viewing each leukodystrophy as an isolated disorder, scientists are beginning to identify shared molecular themes. Defects in transcription, RNA processing and translation can converge on common biological outcomes, including impaired myelin maintenance, cellular stress, disrupted organelle function and altered communication between neurons and glial cells. This convergence may help explain why mutations in very different genes can produce similar patterns of white matter injury and could reveal treatment strategies that apply across multiple diagnoses.
Therapeutic development remains challenging, but the expanding molecular framework is creating new opportunities. Genetic therapies may eventually replace, silence or correct harmful variants in selected conditions. RNA-based approaches could restore normal splicing, stabilize defective transcripts or adjust gene expression. Small molecules might improve protein production, reduce cellular stress or compensate for downstream metabolic disturbances. Supportive care, rehabilitation and early management of seizures or movement disorders remain important, but the long-term goal is to intervene before irreversible loss of myelin and neural tissue occurs.
By placing transcription, RNA processing and translation at the center of white matter biology, the review emphasizes that these diseases are not simply disorders of myelin. They are also disorders of information flow: the failure to accurately copy genetic instructions, prepare them for use or translate them into the proteins required by brain cells. Understanding how these fundamental errors produce selective damage to the nervous system could transform diagnosis and treatment. As genomic technologies identify more disease-causing variants, the challenge will be to connect each mutation to its molecular consequences—and to turn that knowledge into therapies for patients whose conditions have long remained unexplained.
Subject of Research: Hereditary white matter disorders caused by defects in transcription, RNA processing and translation
Article Title: White matter disorders at the intersection of transcription, RNA processing and translation
Article References: Chapleau, A., Villa Tobón, F. & Bernard, G. “White matter disorders at the intersection of transcription, RNA processing and translation.” Nature Reviews Neurology (2026). https://doi.org/10.1038/s41582-026-01248-1
Image Credits: AI Generated
DOI: 10.1038/s41582-026-01248-1
Keywords: leukodystrophies, hereditary white matter disorders, leukoencephalopathies, transcription, RNA processing, translation, protein biosynthesis, myelin, neurogenetics, central nervous system
