Heterozygous FGF14 variants are associated with spinocerebellar ataxia type 27 (SCA27) [4] and episodic ataxia (EA) [5], although some individuals display milder phenotypes, including tremor without ataxia [5] or nystagmus with occasional episodes of vertigo and incoordination [6]. This evidence concerns the gene FGF14 and Nystagmus.