However, CNV analysis has only reported this single deletion in CACNA1A so far in HM, and this type of alteration is more frequently found in episodic ataxia, where the typical pathogenic mechanism is a loss of function of the channel (Riant et al. 2008, 2010b; Labrum et al. 2009; Wan et al. 2011). The gene discussed is CACNA1A; the disease is Familial paroxysmal ataxia.