KCND3 and cerebellar ataxia: In summary, our transcriptomic analysis at an early stage (1.5 months of age) of pathogenesis, prior to the degeneration of Purkinje cells at the age of 3 months (Figure 2A) and the development of an ataxia phenotype at the age of 4 months (Figure 1), provides evidence to gain insights into the molecular mechanism underlying the Kcnd3 F227del mutation and how it causes SCA22.