A biallelic pentanucleotide repeat expansion (AAGGG) in the poly(A) tail of an AluSx3 transposable element in the replication factor C subunit 1 (RFC1) gene is a frequent cause of cerebellar ataxia, neuropathy, and vestibular areflexia syndrome (CANVAS)1. Here, RFC1 is linked to cerebellar ataxia.