Spinocerebellar Ataxia Type 12
A 68-year-old woman with onset of postural and action hand tremor at age 48, progressing slowly to include gait ataxia at age 58, then dementia at age 65. She had a family history of severe tremor in three of her four siblings, her mother, two maternal uncles, and her maternal grandfather. Her examination also revealed appendicular and gait ataxia, titubation, apraxia, paratonia, and dementia. SCA12, a type of dominant ataxia common in India but rare elsewhere, was confirmed by genetic testing.
Andrew P. Duker, MD