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?. Sca19, SCA22 (caused by KCND3 gene mutations) are rare forms of inherited ataxia

, ? We characterized cognitive and behavioral disorders

, ? KCND3 may be a candidate gene for epilepsy, Parkinsonism and cognitive disorders. SUPPORTING INFORMATION Data S1: Next-generation sequencing

, Gene panel design: A list of the 24 genes associated with dominant hereditary ataxia was selected and included in an SCA panel after analyzing the literature and the OMIM database. Genes with trinucleotide repeat expansions and those associated with SCA were not included in the panel. The gene panel comprised AFG3L2 (SCA28), ATP1A2 (episodic ataxia), vol.1, p.1

, CACNB4 (episodic ataxia type 5), CCDC88C (SCA40), EEF2 (SCA26), ELOVL4 (SCA34), ELOVL5 (SCA38), vol.14, p.1

, ITPR1 (SCA15/16/29), KCNA1 (episodic ataxia type 1), vol.3

, KCND3 (SCA19/22), PDYN (SCA23), PLEKHG4 (SCA4), PRKCG (SCA14), pp.1-3

, SL2A2 (episodic ataxia), SPTBN2 (SCA5), TGM6 (SCA35), TTBK2 (SCA11), and TMEM240 (SCA21). The SCA panel of 24 genes was designed using SureDesign software (v4.5, Agilent Technologies

, Targeted sequencing: Exon capture of the 24 selected genes and libraries was prepared using the Haloplex kit (Agilent Technologies), according to the manufacturer's instructions. Pooled libraries (n=20) prepared using the SCA panel were sequenced on a MiSeq system (Illumina) with MiSeq Reageant kit v2

, Supplemental Figure S1: Electrophoregrams of the heterozygous KCND3 mutation

A. , EEG of patient V-4 in family A revealed short bursts of pointed theta waves in the right frontal region. B. EEG of the patient V-6 in family A showing abundant bursts of bilateral-synchronous spike and waves discharges which are more prevalent in the right frontal region