ATXN2 and spinocerebellar ataxia type 2: We then analysed the genotyping performance across all repeat loci and found that, despite high coverage in most repeats in coding regions, some loci had low genotyping rates, such as those that cause spinocerebellar ataxia 2 (ATXN2, 0.1–8.4%) and Huntington disease (HTT, 0.2–58.2%), depending on the capture kit.