Leukodystrophies: a proposed classification system based on pathological changes and pathogenetic mechanisms

Area of Science:

• Neuroscience
• Genetics
• Pathology

Background:

• Leukodystrophies are genetic white matter disorders with variable onset and clinical course.
• Many are progressive and fatal with no known cure.
• Recent advances in MRI and sequencing have identified numerous leukodystrophies.

Purpose of the Study:

• To propose a novel classification of leukodystrophies based on primary affected white matter component.
• To provide examples illustrating neuropathology and disease mechanisms within this new framework.

Main Methods:

• Review of current knowledge on white matter physiology and pathology.
• Integration of MRI pattern recognition and next-generation sequencing data.
• Development of a classification system based on cellular pathology.

Main Results:

• Identified that many leukodystrophies involve non-myelin/oligodendrocyte components.
• Proposed categories: myelin disorders, astrocytopathies, leuko-axonopathies, microgliopathies, and leuko-vasculopathies.
• Recognized that some disorders fit multiple categories.

Conclusions:

• A cellular pathology-based classification is crucial for understanding leukodystrophies.
• This novel classification aids in identifying primary defects in white matter components.
• Understanding cellular pathology is key to developing effective treatment strategies.