Spinocerebellar ataxia type 2 (part A): epidemiology and clinical and genetic characteristics
Keywords:
Spinocerebellar ataxia type 2, genetic counseling, neuropathology, neurophysiology, CAG repeats, rehabilitationAbstract
Spinocerebellar ataxia type 2 (SCA2) is an autosomal dominant genetic disease characterized
by cerebellar dysfunction associated with slow saccades, early hyporeflexia, severe tremor of
postural or action type, peripheral neuropathy, cognitive disorders, and other multisystemic
features. Currently SCA2 is considered one of the most common ataxias worldwide. SCA2 is
a polyglutamine disease caused by the abnormal expansion of CAG triplet repeat located in
the ATXN2 gene. Affected individuals carry more than 32 and up to several hundred of CAG
repeats. In this review we present a detailed description of epidemiology, clinical, genetic,
electrophysiological and neuropathological characteristics of SCA2. The experience in apply-
ing early molecular diagnosis and a predictive diagnosis program in Cuba have allowed the
establishment of rehabilitation programs for patients with SCA2.
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