Takeaway
Nonsegregation of the transglutaminase 6 gene (TGM6) p.L517W mutation with disease phenotype suggests that the variant is not pathogenic.
In the four-generation pedigree studied, ataxia was likely caused by a CAG expansion in atrophin-1 (ATN1).
Why this matters
Pathogenic mutations in TGM6 have previously been reported in people with spinocerebellar ataxia 35 (SCA35).
Findings from this study challenge the role of TGM6 in SCA35 pathogenesis.