ATXN7 and Onset: Collectively, these findings demonstrate that respiratory motor neuronal pathology likely contributes to death in SCA7-266Q mice, and may partially explain the respiratory pathology observed in human infantile-onset SCA7 (Niu et al., 2018; Noma et al., 2012; Stoyas et al., 2020; Ward et al., 2019; Yoo et al., 2003).