Gerstmann–Sträussler–Scheinker syndrome with early-onset spinocerebellar ataxia phenotype

Abstract

The article presents a description of the family case of rare hereditary prion disease – Gerstmann–Sträussler–Scheinker syndrome with a verified p.P102L mutation in the PRNP gene. The clinical picture was represented by progressive cerebellar ataxia, pyramidal signs, bulbar syndrome, and neuropathy, which made it possible to establish a preliminary diagnosis of autosomal dominant spinocerebellar ataxia. Subsequently, the final diagnosis was verified using the massive parallel sequencing technology. The features of this observation are the variable age of onset within the family, with the unusually early age of the disease onset in the proband (age of 25 years), the absence of cognitive impairment, as well as the absence of pathological changes in the electroencephalography and brain MRI study. The possible modifying role of polymorphism in codon 129 of the PRNP gene (129Val) in the disease phenotype formation, as well as the clinical findings and diagnostic methods of this syndrome are discussed.