Abstract
Ataxia with oculo-motor apraxia type 2 (AOA2) is a recently described autosomal recessive
cerebellar ataxia (ARCA) caused by mutations in the senataxin gene (SETX).
We analysed the phenotypic spectrum of 19 AOA2 patients with mutations in SETX, which seems to be the third most frequent form of ARCA in Algeria after Freidreich
ataxia and Ataxia with vitamin E deficiency. In AOA2 patients, the mean age at onset
for all families was in the second decade. Cerebellar ataxia was progressive, slowly
leading to disability which was aggravated by axonal polyneuropathy present in almost
all the patients. Mean disease duration until wheelchair was around 20 years. Oculo-motor
apraxia (OMA) was present in 32% of the patients while convergent strabismus was present
in 37%. Strabismus is therefore also very suggestive of AOA2 when associated with
ataxia and polyneuropathy even in the absence of OMA. Cerebellar atrophy was more
severe in the eldest patients; however it may also be an early sign since it was present
in the youngest and paucisymptomatic patients. The initial sign was gait ataxia in
all but two patients who presented with head tremor and writer cramp, respectively.
Serum alpha-fetoprotein, which was elevated in all tested patients, was a good marker
to suggest molecular studies of the SETX gene.
Keywords
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Article info
Publication history
Published online: January 13, 2009
Accepted:
December 2,
2008
Received in revised form:
November 21,
2008
Received:
August 18,
2008
Identification
Copyright
© 2008 Elsevier B.V. Published by Elsevier Inc. All rights reserved.
