KIAA2022/NEXMIF c.1882C>T (p.Arg628*) Variant in a Romanian Patient with Neurodevelopmental Disorders and Epilepsy: A Case Report and Systematic Review.

Pathogenic variants in the NEXMIF gene are associated with a broad neurodevelopmental phenotype, including autism spectrum disorder (ASD), intellectual disability (ID), and epilepsy. However, the role of NEXMIF in specific epileptic syndromes remains insufficiently explored. We present the case of an 11.9-year-old Romanian girl diagnosed with ASD, attention-deficit/hyperactivity disorder (ADHD), mild ID, and Jeavons syndrome (generalized epilepsy characterized by eyelid myoclonia, absence seizures, and photosensitivity). Genetic testing identified a pathogenic NEXMIF variant: c.1882C>T (p.Arg628*), a pathogenic variant rarely reported in the literature, with only two documented cases to date. To better understand the genotype-phenotype correlation, we conducted a systematic review of NEXMIF-associated disorders and compared our findings with previously reported cases. Our analysis suggests that NEXMIF variants may contribute to a broader spectrum of epileptic syndromes, including photosensitive epilepsy such as Jeavons syndrome. This highlights the need for a greater awareness of atypical seizure presentations in individuals with NEXMIF-related disorders. This study underscores the importance of genetic testing in individuals with overlapping ASD and epilepsy phenotypes as early diagnosis may facilitate targeted therapeutic interventions and genetic counseling. Further research is needed to clarify the molecular mechanisms linking NEXMIF dysfunction to epileptic syndromes and neurodevelopmental disorders.