In analyzing another SEL1LS658P variant (p.Ser658Pro; c.1972T>C, NM_005065), first reported in 2012 in Finnish Hound suffering cerebellar ataxia with uncertain causality62, we show that this SEL1L variant causes ERAD dysfunction, leading to developmental delay and early onset, non-progressive, cerebellar ataxia in mice. Here, SEL1L is linked to aceruloplasminemia.