|Classification and external resources|
Sagittal section through right cerebellar hemisphere. The right olive has also been cut sagitally.
Olivopontocerebellar atrophy (OPCA) is a term used to define neuronal degeneration in the cerebellum, pontine nuclei, and inferior olivary nucleus. The use of the term has changed considerably in recent years due to the progressing knowledge of the genetic basis of the disease.
The term "olivopontocerebellar atrophy" currently applies only to two hereditary disorders whose genetic basis remains unknown:
|OPCA type 2||258300||Fickler-Winkler type OPCA||autosomal recessive|
|OPCA type 5||164700||OPCA with dementia and extrapyramidal signs||autosomal dominant|
In the past, the term "olivopontocerebellar atrophy" extended to both the sporadic (non-hereditary) cases of the disease, which have been currently reclassified as a form of multiple system atrophy, as well as to four hereditary types, which have been currently reclassified as four different forms of spinocerebellar ataxia:
|Hereditary OPCA type||OPCA name||SCA #||Gene||OMIM|
|OPCA type 1||"Menzel type OPCA"||SCA1||ATXN1||164400|
|OPCA type 2, autosomal dominant||"Holguin type OPCA"||SCA2||ATXN2||183090|
|OPCA type 3||"OPCA with retinal degeneration"||SCA7||ATXN7||164500|
|OPCA type 4||"Schut-Haymaker type OPCA"||SCA1||ATXN1||164400|