The molecular and neuro-ophthalmological features of autosomal recessive spastic ataxia of Charlevoix-Saguenay (ARSACS)

The inherited ataxias and spastic paraplegias are genetically highly heterogeneous and reaching a confirmed molecular diagnosis remains challenging. Autosomal recessive spastic ataxia of Charlevoix-Saguenay (ARSACS) is a relatively rare subtype that was first described among French Canadian patients from Qubec presenting with a stereotypical triad of early-onset cerebellar ataxia, spastic paraplegia and peripheral neuropathy. Pathogenic mutations in the SACS gene were subsequently identified in these families. Although retinal hypermyelination was originally reported as a characteristic disease manifestation, the actual nature and frequency of these abnormal retinal findings in ARSACS has recently been disputed.