Rattibha

Hereditary Ataxias!!!
Spinocerebellar ataxias (SCA)
“SCA1 …. the unstable CAG trinucleotide repeat expansion”
American geneticist Harry T. Orr
#MedTwitter #neurotwitter #EndNeurophobia #tweetorials
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SCA definition
“complex group of heterogeneous degenerative diseases of the cerebellum and its connections”
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Worldwide distribution of SCA subtypes
21% SCA3, Brazil & Portugal
15% SCA2, India & Singapore
15% SCA6, Japan & Germany
6% SCA1, South Africa
5% SCA7, South Africa
3% SCA8, worldwide
<1% rare
SCA 10, SCA 12, SCA 14, SCA17
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SCA1
“ophthalmoplegia + spasticity + extrapyramidal signs”
- ATXN1, AD
- anticipation w/ paternal transmission
- 1st identified
- best understood at molecular level
doi.org via: Movement Disorders: A Video Atlas
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doi.org

SCA2
“early slow oculomotor saccades, ophthalmoplegia, fasciculations, extrapyramidal signs”
- infantile, onset
- associated w/ dementia & muscle cramping
- ATXN2, AD
- anticipation w/ paternal transmission
- Cuban population
doi.org via: Mov Disord
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doi.org

SCA3
“ophthalmoplegia, vestibular involv, fasciculations, neuropathy, spasticity, extrapyramidal signs”
-severe vertigo & muscle cramping
-Machado-Joseph disease
-most freq SCA
-Portuguese pop
-anticipation w/ paternal transmission
doi.org via: Mov Disord
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doi.org

SCA6
“downbeat nystagmus & vestibular involvement”
- after age 50y, onset
- episodic ataxia
- severe vertigo
- CACNA1A
- anticipation is not seen
doi.org via: Mov Disord
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doi.org

SCA7
“early slowed oculomotor saccades, spasticity”
- infantile onset
- associated w/ seizure & retinopathy
- macular dystrophy
doi.org via: Mov Disord
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doi.org

SCA8
“saccadic dysmetria and gaze-evoked nystagmus”
- mild disease
- ATXN 8, ATXN8 OS
- AD
- maternal anticipation
collections.lib.utah.edu via: UTAH
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