CD68 and spinocerebellar ataxia type 2: In cerebellar variant of multiple system atrophy and spinocerebellar ataxia type 2, the pontine basis and the corticospinal tracts are the areas mostly affected by degeneration, together with the cerebellum and middle cerebellar peduncles.72-75 This could explain the upregulation in CD68 expressing cells we measured in the pons in the non-GA ataxia control group as a potential response to axonal degeneration and synaptic loss.76,77