Prevalence of intronic repeat expansions in RFC1 in Dutch patients with CANVAS and adult-onset ataxia

Abstract Recently, an intronic biallelic (AAGGG) n repeat expansion in RFC1 was shown to be a cause of CANVAS and adult-onset ataxia in multiple populations. As the prevalence of the RFC1 repeat expansion in Dutch cases was unknown, we retrospectively tested 9 putative CANVAS cases and two independent cohorts (A and B) of 395 and 222 adult-onset ataxia cases, respectively, using the previously published protocol and, for the first time optical genome mapping to determine the size of the expanded RFC1 repeat. We identified the biallelic (AAGGG) n repeat expansion in 5/9 (55%) putative CANVAS pa... Mehr ...