Currently, POLR3A, POLR3B, OTUD4, STUB1, PNPLA6, and RNF216 are all genes associated with CHH syndromes and cerebellar ataxia, with clinical manifestations that can vary and may present with infant or adult onset [17,18,19,20,21,22]. Here, OTUD4 is linked to cerebellar ataxia.