PURPOSE OF REVIEW:
More than 100 heritable disorders can present with abnormal white matter on neuroimaging. While acquired disorders remain a more common cause of leukoencephalopathy in the adult than genetic causes, the clinician must remain aware of features that suggest a possible genetic etiology.
The differential diagnosis of heritable white matter disorders in adults has been revolutionized by next-generation sequencing approaches and the recent identification of the molecular cause of a series of adult-onset disorders.
The identification of a heritable etiology of white matter disease will often have important prognostic and family counseling implications. It is thus important to be aware of the most common hereditary disorders of the white matter and to know how to distinguish them from acquired disorders and how to approach their diagnosis.