Biallelic Mutation of SETX and Additional Likely “In Cis” SETX Sequence Change in Ataxia with Oculomotor Apraxia Type 2

Abstract

Ataxia with oculomotor apraxia type 2 (AOA2) is a slowly progressive, autosomal recessive disease characterized by the triad of ataxia, oculomotor apraxia, and sensorimotor neuropathy. The genetic basis of AOA2 is biallelic mutation of the SETX gene, resulting in reduced or absent senataxin, a DNA/RNA repair protein essential for genomic stability.

In this case report, we described a case of AOA2 with two clear pathogenic SETX mutations, one of which is novel. We then discussed two further likely “in cis” SETX sequence changes (previously reported in the literature as pathogenic), and presented the case that they are likely benign polymorphisms.

Keywords

AOA2 - senataxin - ataxia

^∗ Current Address of the Author: Royal United Hospital Bath NHS Foundation Trust, Department of Postgraduate Medical Education, Bath, United Kingdom.

Publication History

Received: 30 April 2020

Accepted: 27 May 2020

Article published online:
20 July 2020

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