SCN1B and cerebellar ataxia: Three likely pathogenic variants in these genes were identified in Case-21 (CACNA1E p.Ile614Val), Case-25 (SCN1B p.Cys121Trp), and Case-31 (SCN9A p.Tyr1217Ter), with very late onset of ataxia at the age of 60, 59, and 56, respectively.