Mutations in the gene encoding SETX, also known as Senataxin, are mainly linked to two distinct neurodegenerative diseases, a cerebellar ataxia known as oculomotor apraxia type 2 (AOA2) and a form of juvenile amyotrophic lateral sclerosis, ALS4 (Chen et al., 2004;Moreira et al., 2004). SETX is an RNA/DNA helicase that functions in multiple events related to RNA metabolism and DNA maintenance, including transcriptional termination at certain genes and the DNA damage response at replication stress foci.