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The elongator complex is a highly conserved macromolecular assembly composed by 6 individual proteins (Elp 1–6) and it is essential for many cellular functions such as transcription elongation, histone acetylation and tRNA modification. ELP2 is the second major subunit and with Elp1 and Elp3 it shapes the catalytic core of this essential complex. ELP2 gene pathogenic variants have been reported to be associated with several neurodevelopmental disorders, such as intellectual disability, severe motor development delay with truncal hypotonia, spastic diplegia, choreoathetosis, short stature and neuropsychiatric problems. Here we report a case with heterozygous variants of the ELP2 gene associated with unpublished electro-clinical and neuroimaging features, such as abnormal eye movements, focal epilepsy, cortico-cerebellar atrophy and nodular cortical heterotopia on brain MRI. A possible phenotype-genotype correlation and the electro-clinical and neuroimaging phenotype expansion of ELP2 mutations are here discussed, together with considerations on involved cortico-cerebellar networks and a detailed review of the literature.

Weiss-Kruszka syndrome is a recently described genetic disorder characterized by craniofacial features, ptosis, dysgenesis of the corpus callosum, and neurodevelopmental impairment. It is caused by heterozygous loss-of-function variantsin ZNF462 gene. During the time, the original phenotype was expanded, including several complications, sensorineural hearing loss, congenital hypogonadotropic hypogonadism with anosmia and complete growth hormone deficiency associated with empty sella syndrome. Here we report the first case of Weiss-Kruszka syndrome, associated to a de novo 9q31.1q31.3 microdeletion showing an acute lymphoblastic leukemia. A speculation on the contribution of our case to the phenotypic expansion of WSKA is here discussed. More clinical and functional studies are needed to elucidate this association. A possible expansion of the WSKA phenotype is discussed.

Objective: This review article focuses on clinical and genetic features of paroxysmal neurological disorders featuring episodic ataxia (EA) and epilepsy and help clinicians recognize, diagnose, and treat patients with co-existing EA and epilepsy. It also provides an overview of genes and molecular mechanisms underlying these intriguing neurogenetic disorders. Methods: Based on a literature review on Pubmed database, a list of genes linked to paroxysmal neurological disorders featuring EA and epilepsy were compiled. Online Mendelian Inheritance in Man (OMIM) was used to identify further reports relevant to each gene. Results: Among the various forms of EAs, only EA1 (KCNA1), EA2 (CACNA1A), EA5 (CACNB4), EA6 (SLC1A3), and EA9 (SCN2A) phenotypes with associated epilepsy have been described. Next-generation sequencing (NGS) has helped in the identification of other genes (e.g.: KCNA2, ATP1A3, SLC2A1, PRRT2) which have shown an overlapping phenotype with EA and epilepsy. Conclusion: Overlapping clinical features between EA and epilepsy may hinder an accurate classification, and complex genotype-phenotype correlation may often lead to misdiagnosis. NGS has increased the awareness of common genetic etiologies for these conditions. In the future, extensive genetic and phenotypic characterizations can help us to elucidate the boundaries of a wide phenotypic spectrum. These insights may help develop new precision therapies in paroxysmal neurological disorders featuring EA and epilepsy.