Inheritance: autosomal recessive or sporadic
Gene affected: senataxin (SETX)
Chromosome location: 9q34
Clinical features:
(1) onset during adolescence
(2) slowly progressive cerebellar ataxia, which usually presents with gait ataxia
(3) oculomotor apraxia and/or convergent strabismus
(4) axonal polyneuropathy
Laboratory findings:
(1) elevation in serum alpha-fetoprotein (AFP)
Imaging findings:
(1) Cerebellar atrophy may be present at symptom onset or develop over time.
Differential diagnosis:
(1) paraneoplastic syndrome
(2) other hereditary ataxia (Friedreich's ataxia, etc)
