Results suggest that ICpeptides may be used to modulate calcium release in various IP3R1-associated ataxias (ataxias in which IP3R1 is less abundant, e.g., SCA15/SCA16 as well as SCA1 and SCA3, or more sensitive than in wild type mice or unaffected individuals, e.g., SCA2 and SCA3 and likely SCA1). Here, ATXN2 is linked to cerebellar ataxia.