ARX and epilepsy: Although, the majority of genes associated with epilepsies are coding for different voltage and ligand-gated ion channels or regulating the action of excitatory or inhibitory neurotransmission (i.e., CHRNA4, CHRNA2, CHRNB2, GABRG2, GABRA1, KCNQ2, KCNQ3, SCN1B, SCN1A, SCN2A), the potential role of several other genes (i.e., ARX, CDKL5, LGI1, PCDH19, SLC2A1, SPTAN1, STXBP1) in the epilepsy has also been also suggested (Rees, 2010; Hildebrand et al., 2013).