Our in-depth phenotyping highlights that the spectrum of RFC1 disease should indeed be conceptualized far beyond the classic ACC and CANVAS clusters, thereby extending previous phenotypic characterizations of RFC1 disease.5 Specifically, we demonstrate that RFC1 disease is predominantly multisystemic beyond CANVAS, including in particular several recurrent features and feature combinations that overlap with and mimic other neurodegenerative diseases. This evidence concerns the gene RFC1 and neurodegenerative disease.