In animal models of spinocerebellar ataxia type 3 (SCA3) and Alzheimer's disease (AD), UBE4B facilitates clearance of ataxin 3 and APP, respectively (Matsumoto et al., 2004; Gireud-Goss et al., 2020). Here, UBE4B is linked to Spinocerebellar ataxia type 3.