Tophaceous gout of the nose in a male FMR1 premutation carrier

Abstract

Fragile X-associated tremor/ataxia syndrome (FXTAS; OMIM 300623) is an adult-onset neurodegenerative disorder that is characterized by intention tremor, cerebellar ataxia, neuropathy, memory deficits, parkinsonian features, central nervous system (CNS) atrophy, and white matter disease. 1 FXTAS is one of the disorders associated with the fragile X premutation which is characterized by the expansion of the non-coding CGG repeat region (55-200 repeats) of the fragile X messenger ribonucleoprotein 1 gene (FMR1). The premutation causes elevated levels of FMR1 mRNA and a subsequent gain-of-function toxicity resulting in the formation of intranuclear inclusions in neurons and astrocytes in numerous brain regions and in the peripheral nervous system. 2