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Familial neurodegeneration in progressive supranuclear palsy

Progressive supranuclear palsy (PSP)1 is a distinctive form of neurodegenerative parkinsonism characterized by ophthalmoparesis, early gait disorder, and deposits of neurofibrillary tangles in the brain, which are mainly composed of hyperphosphorylated microtubule-associated protein tau ( MAPT or tau gene, MIM:157140).

In the last few years, we have learned that many late-onset disorders often have an underlying genetic cause. The mutated genes still to be discovered are those which either have reduced penetrance or produce a heterogeneous phenotypic expression.

PSP has traditionally been considered a sporadic condition, but its consistent genetic association with markers in chromosome 17q21 and the reports of familial PSP cases suggest that family aggregation may be more frequent than reported.

In this issue of Neurology ®, Donker Kaat and colleagues2 present a comprehensive epidemiologic, clinical, and genetic population-based study on familial aggregation of certain neurodegenerative conditions, such as dementia and parkinsonism, in PSP. The most frequent presenting symptom in PSP …