Our results may also provide some insight into the more variable phenotypes and decreased penetrance in spinocerebellar ataxia patients with FGF14 haploinsufficiency (Dalski et al., 2005; Coebergh et al., 2013) vs patients with a FGF14 mutation (FGF14bF150S) found in a large Dutch spinocerebellar ataxia kindred (van Swieten et al., 2003). Here, FGF14 is linked to cerebellar ataxia.