Rare genetic diseases pose significant challenges in diagnosis and treatment due to their complexity and rarity. Next-generation sequencing (NGS) is a revolutionary genomic technology that enables rapid and cost-effective analysis of DNA or RNA sequences on a large scale, allowing for simultaneous sequencing of millions of DNA fragments in parallel. This study presents a comprehensive approach to identifying disease-causing genes and pathways associated with a rare genetic condition in a patient from consanguineous parents. Through clinical evaluation, whole exome sequencing (WES), and advanced bioinformatics analysis, female patient exhibiting mental disability, psychomotor retardation, depressive mood, and seizures since childhood was investigated. WES, followed by variant annotation using QIAGEN Clinical Insight (QCI) software, facilitated the identification of potentially pathogenic variants. Variant prioritization was based on allele frequency, conservation, pathogenicity prediction, and literature review. This integrative approach revealed candidate variants associated with potential disease-causing genes and pathways, providing insights into the molecular mechanisms underlying the rare genetic disorder. Further research is warranted to validate these findings and elucidate the pathophysiology for improved diagnosis and personalized treatment strategies.