OBJECTIVE: Spinocerebellar ataxia type 8 (SCA 8) is an autosomal dominant disorder characterized by cerebellar ataxia with additional features, such as upper motor neuron signs, urinary incontinence and dysphagia. From a clinical standpoint, SCA 8 and the cerebellar form of multiple system atrophy (MSA-C) share several common features. METHODS: We studied the presence of expanded SCA 8 alleles in 10 sporadic patients with probable MSA-C. RESULTS: We found 1 patient with a heterozygous CTA/CTG repeat expansion in the pathological range. Clinically this subject presented no features that differed from the other subjects carrying smaller repeat sizes. CONCLUSIONS: We believe that the association of SCA 8 repeat expansions with sporadic, atypical and heterogeneous phenotypes is debatable and should be interpreted with caution. Our personal conclusion is that testing in such patients may become a source of diagnostic confusion.
OBJECTIVE:Spinocerebellar ataxia type 8 (SCA 8) is an autosomal dominant disorder characterized by cerebellar ataxia with additional features, such as upper motor neuron signs, urinary incontinence and dysphagia. From a clinical standpoint, SCA 8 and the cerebellar form of multiple system atrophy (MSA-C) share several common features. METHODS: We studied the presence of expanded SCA 8 alleles in 10 sporadic patients with probable MSA-C. RESULTS: We found 1 patient with a heterozygous CTA/CTG repeat expansion in the pathological range. Clinically this subject presented no features that differed from the other subjects carrying smaller repeat sizes. CONCLUSIONS: We believe that the association of SCA 8 repeat expansions with sporadic, atypical and heterogeneous phenotypes is debatable and should be interpreted with caution. Our personal conclusion is that testing in such patients may become a source of diagnostic confusion.
Authors: Anna I Wernick; Ronald L Walton; Alexandra I Soto-Beasley; Shunsuke Koga; Michael G Heckman; Rebecca R Valentino; Lukasz M Milanowski; Dorota Hoffman-Zacharska; Dariusz Koziorowski; Anhar Hassan; Ryan J Uitti; William P Cheshire; Wolfgang Singer; Zbigniew K Wszolek; Dennis W Dickson; Phillip A Low; Owen A Ross Journal: Clin Auton Res Date: 2021-01-27 Impact factor: 5.625